isotretinoin and Psoriasis

The potential relationship between systemic retinoids used in dermatology and affective disorders is controversial. Acitretin, which is widely used in the treatment of psoriasis is part of this controversy secondary to its chemical relation to isotretinoin, a drug which has been associated with a large number of anecdotal case reports of depression and suicidal ideation. Moreover, an FDA package insert precaution regarding acitretin's association with depression and suicide has elevated the level of concern for patient safety. The objective of this article is to review the evidence in the literature regarding acitretin's association with affective disorders. After 12 years of worldwide use only two cases involving acitretin have been reported in the literature. In addition, despite many anecdotal cases involving isotretinoin, there have been no clinical studies that have proven a causal relationship between isotretinoin and depression or suicidal ideation. For acitretin there have been no systematic clinical studies that examine such a relationship. Moreover, it is notable that the FDA precaution regarding depression and suicide on the package insert of acitretin predates the publication of the aforementioned two cases. This suggests that a relationship between acitretin and affective disorders is a class labeling rather than a scientifically proven association.

Topics: Acitretin; Depression; Dermatologic Agents; Drug Labeling; Humans; Isotretinoin; Mood Disorders; Psoriasis; Suicidal Ideation; Suicide; United States; United States Food and Drug Administration

Systemic isotretinoin has been used to treat severe acne vulgaris for 20 years. However, isotretinoin also represents a potentially useful choice of drugs in many dermatologic diseases other than acne vulgaris. Diseases such as psoriasis, pityriasis rubra pilaris, condylomata acuminata, skin cancers, rosacea, hidradenitis suppurativa, granuloma annulare, lupus erythematosus and lichen planus have been shown to respond to the immunomodulatory, anti-inflammatory and antitumor activities of the drug. Isotretinoin also helps prevent skin cancers such as basal cell carcinoma or squamous cell carcinoma. A combination of systemic isotretinoin and interferon-alpha-2a may provide a more potent effect than isotretinoin alone in the prevention and treatment of skin cancers.Systemic isotretinoin may be considered as an alternative drug in some dermatologic diseases unresponsive to conventional treatment modalities. However, randomized clinical trials aimed at determining the role of systemic isotretinoin therapy in dermatologic diseases other than acne vulgaris are required.

Topics: Acne Vulgaris; Anti-Bacterial Agents; Anti-Infective Agents; Anti-Inflammatory Agents; Condylomata Acuminata; Dermatologic Agents; Drug Therapy, Combination; Granuloma Annulare; Hidradenitis Suppurativa; Humans; Isotretinoin; Keratolytic Agents; Lichen Planus; Lupus Erythematosus, Systemic; Pityriasis Rubra Pilaris; Psoriasis; Rosacea; Sebaceous Glands; Skin Diseases; Skin Neoplasms

Retinoids have been in sharp focus ever since their introduction 30 years ago. They include any drug (s) that bind to retinoid receptors and elicit a biological response. Enormous information on the subject seems to embroil the recent literature. Practically it is impossible to clearly comprehend the undercurrents. The meticulously dispensing text envisages surmounting the perspective reader's predicaments. Accordingly, retinoids and their related facets namely retinoid receptors, classification, mode of action, and the pharmacological diversity have been precisely defined. Commonly used systemic retinoids too have been given a substantial fresh look along with their monitoring. Overall, adverse effects and relative and absolute contraindications have been scrupulously incorporated. Human immuno deficiency virus (HIV) and isoretinoid for acne, in particular, have been highlighted. Micronized isotretinoin formulations have also been taken care so also commonly used topical retinoids. Tretinoin and their newer formulation have also been accounted for along with tretinoin polymer cream. Adapalene, a new chemical entity possessing a unique physico-chemical activity similar to that of tretinoin has also been dealt with. Newer retinoids are likely to be a subject of intrigue. A focus on future potentials of retinoids is its special ingredient. The inclusion of details of rexinoid the most recent introduction in their purview is likely to invoke interest to further consolidate its reckoning in future. All in all the text of the paper should provide an insight into the current rumbling around retinoids.

Topics: Acne Vulgaris; Adapalene; Administration, Cutaneous; Administration, Oral; Chemistry, Pharmaceutical; Humans; Isotretinoin; Naphthalenes; Psoriasis; Receptors, Retinoic Acid; Retinoids; Skin Diseases; Tretinoin

Systemic retinoids represent a growing armamentarium in the treatment of a wide range of skin disorders and malignancies. Although these drugs can have substantial toxicities, their wise use can result in safe and efficacious therapy that can alter dramatically the lives of individuals with severe skin disorders.

Topics: Acne Vulgaris; Anticarcinogenic Agents; Humans; Isotretinoin; Psoriasis; Retinoids; Skin Diseases; Skin Neoplasms

Isotretinoin (13-cis-retinoic acid) is a retinoid that has been used over the past 2 decades to treat a wide variety of dermatologic conditions, some with great success. Although it is beneficial in many skin conditions, the side effects and toxicities of oral retinoids require careful monitoring by experienced physicians. The clinical applications of oral retinoids continue to expand both within and beyond the field of dermatology.

Topics: Acne Vulgaris; Administration, Oral; Adult; Aged; Aging; Dermatologic Agents; Humans; Isotretinoin; Middle Aged; Psoriasis; Skin Diseases; Skin Neoplasms

Oral retinoids are molecules derived from vitamin A that represent one of the most important steps forward in dermatologic therapeutics in the present century. The treatment of acne, severe psoriasis, and severe disorders of keratinization, prevalent diseases in children and adolescents, have radically changed since the advent of oral retinoids. Like most highly-effective medications, oral retinoids also have important untoward effects. Specialists, and in particular, dermatologists and pediatricians should be prepared to maneuver the delicate balance between therapeutic efficacy and side effects in order to give the pediatric patient the maximum benefit with the lowest possible risk.

Topics: Acne Vulgaris; Adolescent; Child; Humans; Ichthyosis; Infant, Newborn; Isotretinoin; Keratolytic Agents; Male; Psoriasis; Retinoids

The retinoids provide an important new way of treating dermatologic disorders. They have also proved to have a role in the prevention of new lesion formation. New retinoids, of which adapalene is one, have recently been synthesized in order to obtain similar or better efficacy while reducing skin irritation potential. These new molecules are currently under clinical investigation. Preliminary results are encouraging. In the near future, an expanded range of topical retinoids should be available.

Topics: Adapalene; Administration, Cutaneous; Animals; Anti-Inflammatory Agents, Non-Steroidal; Humans; Isotretinoin; Mice; Models, Biological; Naphthalenes; Psoriasis; Retinoids; Skin Aging; Skin Diseases; Tretinoin

Topics: Etretinate; Humans; Isotretinoin; Photosensitivity Disorders; Psoriasis; Retinoids

Topics: Combined Modality Therapy; Etretinate; Humans; Isotretinoin; Psoriasis; PUVA Therapy; Retinoids

Retinoids are potent therapuetic agents that have been found to be effective in a variety of skin diseases. They are of benefit in various forms of severe psoriasis. With severe plaque psoriasis, they are used most effectively in combination with other forms of therapy, such as phototherapy. With generalized pustular psoriasis, they are effective monotherapy and are frequently helpful for the control of exfoliative psoriasis. A variety of new retinoid analogs have been studied in clinical investigations. This article discusses important aspects of the use of etretinate, isotretinoin, acitretin, and arotinoid ethyl ester in the treatment of severe forms of psoriasis.

Topics: Acitretin; Etretinate; Humans; Isomerism; Isotretinoin; Psoriasis; Tretinoin

Topics: Adult; Benzoates; Bowen's Disease; Carcinoma, Basal Cell; Child; Etretinate; Female; Humans; Isotretinoin; Male; Precancerous Conditions; Psoriasis; Retinoids; Skin Diseases; Skin Neoplasms; Tretinoin; Xeroderma Pigmentosum

Topics: Acitretin; Administration, Oral; Benzoates; Eczema; Etretinate; Humans; Isotretinoin; Psoriasis; Retinoids; Skin Diseases; Skin Diseases, Vesiculobullous; Tretinoin

The potential of vitamin A, or retinol, in the treatment of a variety of skin diseases has long been recognized, but because of serious toxic effects this substance generally could not be used. The recent development and marketing of two relatively non-toxic synthetic analogues, which are known as retinoids, has made it possible to treat some of the diseases that are resistant to standard forms of therapy. Isotretinoin is very effective in cystic and conglobate acne, while etretinate is especially useful in the more severe forms of psoriasis. Good results have also been obtained in other disorders of keratinization. Vitamin A and its derivatives apparently have an antineoplastic effect as well and may come to be used in both the prevention and the treatment of epithelial cancer. In many of these diseases the retinoids act by enhancing the normal differentiation and proliferation of epidermal tissues, but the exact mechanisms are not well understood. Their influence on the intracellular polyamines that control the synthesis of nucleic acids and proteins may be an important factor. Although the retinoids have few serious systemic effects, they are teratogenic, and because they persist in the body their use in women of childbearing potential is limited.

Topics: Acne Vulgaris; Bone Diseases; Chemical and Drug Induced Liver Injury; Etretinate; Female; Humans; Isomerism; Isotretinoin; Keratosis; Kinetics; Psoriasis; Skin Diseases; Skin Neoplasms; Tretinoin; Triglycerides; Vitamin A

The retinoids are synthetic derivatives of vitamin A. Isotretinoin (13-cis-retinoic acid) is now being widely used in the United States for severe acne and etretinate is available in Europe and other countries for psoriasis. These drugs are also effective for a number of other skin diseases. This is an attempt to review basic knowledge of retinoids with which the practicing dermatologist should be familiar, to review the current status of studies, and to speculate on the present and future roles of these drugs in dermatology.

Topics: Acne Vulgaris; Etretinate; Humans; Inflammation; Isotretinoin; Keratins; Psoriasis; Retinoids; Sebum; Skin Diseases; Skin Neoplasms; Sweat Gland Diseases; Tretinoin; Vitamin A

Isotretinoin is a new orally active retinoic acid derivative for the treatment of severe refractory nodulocystic acne. The pharmacological profile of isotretinoin suggests that it acts primarily by reducing sebaceous gland size and sebum production, and as a result alters skin surface lipid composition. Bacterial skin microflora is reduced, probably as a result of altered sebaceous factors. Isotretinoin 1 to 2 mg/kg/day for 3 to 4 months produces 60 to 95% clearance of inflammatory lesions in patients with severe, recalcitrant nodulocystic acne, with evidence of continued healing and prolonged remissions in many patients after treatment withdrawal. Doses as low as 0.1 mg/kg/day have also proven successful in the clearance of lesions; however, with such low doses the duration of remission after discontinuation of therapy is usually shorter. Encouraging results have also been seen in small numbers of patients with rosacea, Gram-negative folliculitis, Darier's disease, ichthyosis and pityriasis rubra pilaris, the response in keratinising disorders resembling that with the related drug etretinate. While long term follow-up studies in these patients have not been reported, prolonged remission after withdrawal of isotretinoin in disorders of keratinisation is unlikely, as with other drugs used in these conditions. Isotretinoin is only partially effective in psoriasis, in contrast to etretinate which is very effective in psoriasis but ineffective in severe acne. Some encouraging results have also been reported with isotretinoin in patients with squamous and basal cell carcinomas, but isotretinoin has proven unsuccessful in non-squamous cell epithelial and non-epithelial cancer. Side effects affecting the mucocutaneous system occur in nearly all patients receiving isotretinoin, but rarely lead to drug withdrawal. Raised serum triglyceride levels are also commonly reported. The possibility of long term spinal or skeletal bone toxicity may restrict the use of isotretinoin in severe disorders of keratinisation requiring prolonged administration. Isotretinoin is strictly contraindicated in women of childbearing potential due to its severe teratogenic properties, unless an effective form of contraception is used. Thus, isotretinoin offers an effective advance on the treatment options available in a difficult therapeutic area - those patients with severe, nodulocystic acne not responding to 'traditional' therapy.

Topics: Acne Vulgaris; Animals; Anti-Inflammatory Agents; Carcinogens; Cell Differentiation; Cell Division; Humans; Immunity; Isotretinoin; Kinetics; Mutagens; Psoriasis; Rosacea; Sebaceous Glands; Skin; Skin Absorption; Skin Diseases; Skin Neoplasms; Teratogens; Tissue Distribution; Tretinoin

Topics: Acne Vulgaris; Adolescent; Child; Child, Preschool; Darier Disease; Etretinate; Female; Humans; Ichthyosis; Infant; Isomerism; Isotretinoin; Keratins; Keratoderma, Palmoplantar; Male; Pityriasis Rubra Pilaris; Psoriasis; Skin Diseases; Skin Diseases, Vesiculobullous; Tretinoin

Oral retinoids obviously influence dermal components such as cutaneous capillaries and dermal inflammatory cells in addition to their well-known action on keratinizing epithelia. On this basis, they act as an anti-inflammatory drug. In particular, they reduce the elevated skin temperature, inhibit the motility of neutrophils and eosinophils and their migration into the epidermis, decrease DNA synthesis of human lymphocytes by blocking their response to lectins and stimulate Langerhans cells, monocytes and macrophages in various in vitro and in vivo models. These data indicate that oral retinoids may not only normalize disorders of keratinization but also exert distinct therapeutic effects on various skin diseases with dermal inflammatory involvement regardless of their particular aetiology. In some respects, retinoids resemble corticosteroids, acting as a modified hormone. Preliminary clinical experiences with oral retinoid treatment in skin diseases such as cutaneous disseminated LE, bullous pemphigoid, Duhring's disease, pemphigus, Behçet's disease and necrotizing vasculitis with eosinophilia support these data. Monotherapy or combined administration of oral retinoids with corticosteroids in low doses seems therapeutically beneficial in these disorders.

Topics: Acitretin; Administration, Oral; Animals; Anti-Inflammatory Agents; Etretinate; Granulocytes; Humans; Isotretinoin; Leukocyte Count; Lymphocytes; Macrophages; Mice; Psoriasis; Skin Diseases; Skin Temperature; Tretinoin

The synthetic retinoids are a new class of drugs which are highly effective in the treatment of a broad spectrum of dermatologic disease. In this report 15 patients with chronic disorders of keratinization and one patient with severe cystic acne were treated with oral isotretinoin. The degree of clinical response and duration of post-treatment remission varied with the different disorders. Acute side effects were predominantly limited to the skin and mucous membranes and were reversible after discontinuation of treatment in these patients. Acute retinoid toxicity and the potential for developing chronic toxicity are reviewed. In an attempt to facilitate the monitoring of dermatologic patients treated with oral synthetic retinoids, we present our current guidelines for the use of these agents.

Topics: Acne Vulgaris; Adolescent; Animals; Bone Diseases; Child; Child, Preschool; Etretinate; Humans; Isomerism; Isotretinoin; Joint Diseases; Keratosis; Mice; Psoriasis; Skin Diseases; Tretinoin

Topics: Acne Vulgaris; Administration, Oral; Adolescent; Dermatitis, Exfoliative; Half-Life; Humans; Ichthyosis; Isotretinoin; Neoplasms; Pityriasis Rubra Pilaris; Psoriasis; Tretinoin

Isotretinoin has been used in combination with oral psoralen + UVA (PUVA) and narrowband UVB (NBUVB) for treating psoriasis, especially in women of child-bearing age. The efficacy of oral psoralen + sun exposure (PUVAsol) is comparable to that of PUVA. This study was planned to compare the efficacy of oral PUVAsol with that of the combination of oral isotretinoin and PUVAsol in patients with chronic plaque psoriasis.. Forty patients with psoriasis vulgaris were randomized to two groups. Group A (control group) received PUVAsol only. Group B (intervention group) received PUVAsol + isotretinoin (0.5 mg/kg/day). Psoriasis Area Severity Index (PASI) score was recorded at baseline and weeks 4, 8 and 12. Dermatology Life Quality Index was assessed at baseline and 12 weeks. The end point of the study was PASI 75 or 12 weeks, whichever came earlier.. Thirty-five patients completed the study. There were statistically significant differences between the two study groups for the number of patients achieving the endpoint of PASI 75, PASI scores at the end of 12 weeks, mean duration to achieve PASI 75, number of PUVAsol sessions needed to achieve PASI75 and mean cumulative dosage of 8-methoxypsoralen needed to achieve PASI 75.. The combination of isotretinoin with PUVAsol is more effective compared with PUVAsol alone for treating chronic plaque psoriasis.

Topics: Adult; Aged; Combined Modality Therapy; Female; Furocoumarins; Hospitals; Humans; Isotretinoin; Male; Middle Aged; Photosensitizing Agents; Phototherapy; Psoriasis; Sunlight; Young Adult

Isotretinoin is a retinoic acid frequently used in monotherapy or combined with narrow-band ultraviolet B (NBUVB) irradiation to treat patients with acne and psoriasis vulgaris. As both diseases need frequent and/or prolonged therapeutic interventions, the study of the genotoxicity of retinoids becomes important. Our aim was to study the genotoxic effects of isotretinoin alone or combined with NBUVB. In vitro studies were performed in the absence of S9 metabolic activation using blood from five healthy volunteers, incubated 72 h with isotretinoin (1.2-20 μM) (i.e., at concentrations usually achieved in blood with therapeutic doses as well as at higher concentrations). In vivo studies were also performed using blood from two patients with acne and three patients with psoriasis vulgaris treated with isotretinoin in monotherapy (8 or 20mg/day) or combined with NBUVB (20mg isotretinoin/day+NBUVB). The genotoxic effect was evaluated by the cytokinesis-blocked micronucleus and the comet assays. Our studies showed that isotretinoin alone was not genotoxic when tested in human lymphocytes in vitro and in vivo. There was no clear genotoxic effect in psoriatic patients treated with isotretinoin and NBUVB. The in vitro studies showed that isotretinoin induced apoptosis and necrosis in human lymphocytes at higher doses.

Topics: Acne Vulgaris; Adult; Apoptosis; Cells, Cultured; Combined Modality Therapy; Comet Assay; Cytokinesis; Dermatologic Agents; Female; Humans; Isotretinoin; Lymphocytes; Male; Micronucleus Tests; Necrosis; Psoriasis; Ultraviolet Rays

In this randomized clinical trial, 39 patients with psoriasis vulgaris were randomized in two groups. Intervention group received narrow band ultraviolet B (NBUVB)+isotretinoin (0.5 mg/kg/day), control group received NBUVB+placebo. Psoriasis Area Severity Index (PASI) scoring was recorded at baseline and weeks 4, 10, and 14. Thirty-seven patients completed the study. According to recorded PASI scores the difference between efficacies of two treatments was not significant. Complete clearing was noticed in 14 and 13 patients in intervention group and controls. The mean cumulative NBUVB dose in intervention group and controls was 29.95 ± 16.11 vs. 45.77 ± 7.72J/cm(2) (P=0.004). Isotretinoin+NBUVB can reduce number of phototherapy sessions and cumulative NBUVB dose.

Topics: Adult; Dermatologic Agents; Female; Humans; Isotretinoin; Laser Therapy; Male; Middle Aged; Psoriasis

Topical retinoids are of potential value in the treatment of psoriasis. The aim of the present study was to find out whether topical application of 13-cis-retinoic acid (13-cis-RA) has an antipsoriatic effect. Nine patients participated in the investigation. In each patient, two comparable psoriatic lesions (5 x 5 cm or more) were selected for treatment with either 13-cis-RA in a 0.1% cream base or with the vehicle only (placebo), using a double-blind approach. The investigation was a left-right within-subject comparison. The lesions were recorded for clinical scores 4 weeks before and after the investigation. Punch biopsies were taken from eight patients before and after treatment and examined using immunohistochemical methods to assess epidermal proliferation and keratinization, and to assess inflammation. Thirteen-cis-RA treatment resulted in a mild decrease of scaling and induration. Erythema however increased. No statistically significant difference in biological effects was achieved between 13-cis-RA and placebo treated lesions and no changes in expression of the immunohistochemical markers were seen.

Topics: Administration, Topical; Adult; Aged; Double-Blind Method; Female; Humans; Isotretinoin; Male; Middle Aged; Psoriasis

Topics: Humans; Isomerism; Isotretinoin; Photochemotherapy; Psoriasis; PUVA Therapy; Tretinoin

Topics: Etretinate; Humans; Isomerism; Isotretinoin; Photochemotherapy; Psoriasis; PUVA Therapy; Tretinoin

Orally administered retinoids are synthetic derivatives of vitamin A. This new group of drugs (not yet available for general use in the United States) has been effective in experimental trials for treatment of a wide range of skin diseases. The current status of two of these drugs, isotretinoin (13-cis-retinoic acid) and etretinate (Ro 10-9359), is herein reviewed.

Topics: Acne Vulgaris; Administration, Oral; Child; Clinical Trials as Topic; Facial Dermatoses; Female; Humans; Isomerism; Isotretinoin; Keratins; Keratitis; Neoplasms; Psoriasis; Skin Diseases; Tretinoin; Xerostomia

Topics: Clobetasol; Dermatologic Agents; Diagnosis, Differential; Eosinophilia; Humans; Hydroxyzine; Isotretinoin; Male; Middle Aged; Pityriasis Rubra Pilaris; Psoriasis; Severity of Illness Index; Skin; Treatment Outcome; Urea

The project was aimed at development of isotretinoin nail lacquer and assessment of its penetration efficiency across human nail plate. Preliminary studies (hydration enhancement factor and SEM) aided the selection of thioglycolic acid as permeation and eugenol was selected as local anesthetic in the formulation. The nail lacquer was optimized by 3(2) factorial design and a total of nine formulations were prepared and screened. In vitro adhesion and ex vivo permeation (cumulative drug permeation per unit area (CDP/A) = 6.61 ± 0.57 mg/cm(2)) across bovine hoof guided the selection of F3 as optimized formulation that was improvised. Viscosity adjustments to improve handling characteristics were affected by incorporation of ethyl cellulose (6%; F3M1) that scaled the viscosity to 312.681 cp and insignificantly (p > 0.05) affected CDP/A (6.32 ± 0.45 mg/cm(2)). In comparison to marketed preparation (Retino-A cream) F3M1 afforded two fold increase in CDP/A. The permeation characteristics were defined by Higuchi model (r(2) = 0.964) and flux value of 176 μg/cm(2)/h. Confocal laser scanning microscopy, after 72 h of nail lacquer application, revealed extensive distribution of the fluorescent tracer across the human nail plate in comparison to control that was confined to the top layer. Conclusively, an efficacious and stable nail lacquer of isotretinoin was developed for potential clinical topical use to target the drug to nail bed in treatment of nail psoriasis.

Topics: Administration, Topical; Adult; Animals; Cattle; Dermatologic Agents; Dosage Forms; Drug Stability; Hoof and Claw; Humans; Isotretinoin; Nail Diseases; Nails; Permeability; Psoriasis; Young Adult

Variably considered as a localized subtype of pustular psoriasis, palmoplantar pustulosis (PPP) is commonly treated with topical steroids, acitretin, and local phototherapy with oral or topical psoralen (PUVA). The utility of acitretin for PPP is limited by adverse effects such as myalgias and an extended risk of teratogenicity in female patients. Isotretinoin is a more tolerable retinoid with a shorter teratogenic window, but to date its effectiveness in PPP has not been reported. Herein we present two patients with PPP who responded well to isotretinoin treatment.. Two patients with PPP refractory to topical therapies were started on acitretin. Both patients developed adverse effects (including headache, myalgias, and mood alterations) leading to acitretin discontinuation. Isotretinoin monotherapy was started in one patient resulting in significant clearing of palmar plaques and scale, and the addition of isotretinoin to UVA therapy resulted in near-complete clearing of recalcitrant plantar plaques in the second patient.. Acitretin represents an important treatment for PPP, but is limited by adverse effects and extended teratogenicity. Our experience supports the utility of isotretinoin as a potential therapeutic alternative, which may be particularly beneficial in patients who are poor candidates for or unable to tolerate acitretin therapy.

Topics: Acitretin; Anti-Inflammatory Agents; Biopsy; Calcitriol; Ceramides; Cholesterol; Clobetasol; Combined Modality Therapy; Diagnostic Errors; Drug Combinations; Drug Substitution; Eczema; Emollients; Fatty Acids; Female; Humans; Isotretinoin; Male; Middle Aged; Psoriasis; Ultraviolet Therapy

Topics: Acne Vulgaris; Animals; Calgranulin A; Calgranulin B; Complement C3; Dermatologic Agents; Drug Eruptions; Female; Gene Expression Regulation; Humans; Isotretinoin; Male; Psoriasis

The chemoprevention refers to the use of various types of chemical agents for preventing carcinogenic progression. Systemic retinoids are the most studied chemopreventive agents due to their capacity to regulate cell proliferation and their demonstrated efficacy in several clinical studies.. The aim of the authors was to give precise indications regarding the use of the systemic retinoid in the chemoprevention of non-melanoma skin cancer (NMSC).. The authors reviewed the literature found through a search to MEDLINE (from 2001 to December 2011).. Both acitretin and isotretinoin are effective for the prevention of NMSC. Isotretinoin is preferred in xeroderma pigmentosum and nevoid basal cell carcinoma syndrome, whereas acitretin is more used in transplant recipients, psoriasis and severe sun damage.. Despite numerous studies of the literature concerning retinoids in chemoprevention of NMSC, precise details of the type of retinoid to use, dosage and the duration of this preventive treatment and how to manage side effects in the case of long-lasting treatment are still not uniform and comparable. Moreover, neither guidelines nor approval by Food and Drug Administration exist to regulate the use of retinoids in chemoprevention.

Topics: Acitretin; Basal Cell Nevus Syndrome; Dermatologic Agents; Humans; Isotretinoin; Off-Label Use; Organ Transplantation; Psoriasis; Risk Factors; Skin Neoplasms; Sunlight; Xeroderma Pigmentosum

Topics: Dermatologic Agents; Humans; Inflammatory Bowel Diseases; Isotretinoin; Psoriasis; Skin Diseases; Skin Neoplasms

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a clinically heterogeneous entity, encompassing a variety of debilitating conditions that have in common inflammation of the skeletal system and skin. To date, there is a paucity of documented efficacious treatment options. We report a 48-year-old man with skeletal and cutaneous signs and symptoms who improved dramatically after treatment with a combination of isotretinoin and pamidronate. This report provides an alternative treatment regimen for SAPHO that addresses the possible underlying pathophysiology of this likely underdiagnosed syndrome.

Topics: Acneiform Eruptions; Diphosphonates; Drug Therapy, Combination; Humans; Hyperostosis; Isotretinoin; Male; Middle Aged; Osteitis; Pamidronate; Psoriasis; Skin Diseases; Syndrome; Synovitis

Topics: Adalimumab; Adult; Anti-Inflammatory Agents; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Arthritis, Rheumatoid; Dermatologic Agents; Etanercept; Female; Flurandrenolone; Foot; Hand; Humans; Immunoglobulin G; Isotretinoin; Keratolytic Agents; Methotrexate; Middle Aged; Prednisone; Psoriasis; Receptors, Tumor Necrosis Factor; Skin; Tumor Necrosis Factor-alpha

The association between exposure to Isotretinoin, the development of depression and suicide attempts is controversial.. To retrospectively assess pattern of utilization of mental health services in the Israeli Defense Forces (IDF) during a 5-year period for all subjects exposed to Isotretinoin in comparison to a control group consisting of army conscripts suffering from psoriasis. All subjects were young adults (18 to 21 years old) in compulsory military service.. Exposure to Isotretinoin mandates reporting and marking as a coded medical profile in the IDFs' computerized medical record of each conscript and soldier. Medical data, tracked by military medical profiles, were summarized from medical records of all subjects treated by Isotretinion during the years 1999-2003 and for the control group for the same period. Use of mental health services was the a-priori defined primary outcome measure.. During the study period 1419 subjects were exposed to Isotretinoin and 1102 suffered from psoriasis. Utilization of mental health services was highest for the index group wherein 17.2% (245/1419) of subjects were evaluated or treated compared to 12.5% in the control group (psoriasis). The inter-group differences were statistically significant; Chi-square=15.9 (df=2), p=0.0003.. We suggest that psychiatric evaluation be regularly undertaken prior to initiation of Isotretinion treatment in young adults at risk, as well as providing follow-up visits during and at completion of treatment.

Topics: Acne Vulgaris; Adolescent; Adult; Female; Health Services; Humans; Isotretinoin; Israel; Male; Mental Disorders; Mental Health Services; Military Personnel; Psoriasis; Retrospective Studies

Topics: Abortion, Induced; Adult; Dermatitis Herpetiformis; Diagnosis, Differential; Female; Humans; Isotretinoin; Keratolytic Agents; Photochemotherapy; Prednisolone; Pregnancy; Pregnancy Complications; Pregnancy Trimester, Second; Psoriasis

Small open studies of patients at high risk for squamous cell carcinoma (SCC) of the skin suggest that oral retinoid use reduces the risk of these tumors. Among patients at lower risk, randomized trials of low doses of retinoids did not demonstrate significant chemopreventive effects. Patients with psoriasis treated with oral psoralen-UVA have a high risk of SCC development. Oral retinoids are used to treat psoriasis. We performed a nested cohort study to assess whether oral retinoids reduce skin cancer risk among patients with psoriasis exposed to psoralen-UVA.. From 1985 to 2000, 135 patients (11.3% of surviving patients in our cohort) used retinoids for at least 26 weeks in 1 year or more. For these 135 patients, we compared each person's SCC and basal cell carcinoma incidence during years of substantial oral retinoid use and other years. We used Poisson regression models to adjust for potential confounders.. In a paired analysis, which compared each patient's own tumor experience while using and not using retinoids, retinoid use was associated with a 30% reduction in SCC incidence (196 SCCs/1000 and 302 SCCs/1000 years of use and no use, respectively; P =.002). After adjusting for other factors associated with SCC risk, the incidence of SCC was significantly decreased during years of substantial retinoid use (incidence rate ratio = 0.79; 95% confidence interval = 0.65, 0.95). Oral retinoid use and basal cell carcinoma incidence were not significantly associated.. In patients with psoriasis treated with psoralen-UVA, systemic retinoid use reduced SCC risk but did not significantly alter basal cell carcinoma incidence.

Topics: Adult; Carcinoma, Basal Cell; Carcinoma, Squamous Cell; Case-Control Studies; Chemoprevention; Female; Humans; Incidence; Isotretinoin; Male; Middle Aged; Multivariate Analysis; Prospective Studies; Psoriasis; PUVA Therapy; Retinoids

Psoriasis treatment requires consideration of patient-specific concerns in addition to the severity of skin involvement. There may be sex-specific differences in the treatment of severe psoriasis.. The purpose of this study was to determine whether there are sex-specific differences in the treatment of severe psoriasis.. We analyzed the medications prescribed to patients with a primary and only diagnosis of psoriasis recorded in the 1990-1994 National Ambulatory Medical Care Survey.. There were 8.5 million visits to physicians for the treatment of psoriasis in the years 1990-1994. These visits were made by approximately 4.3 million women and 4.1 million men. Only 39% of patients receiving systemic treatments were women. Women received less methotrexate (23% women) and etretinate (35% women) than men, but more psoralen photochemotherapy (PUVA) (63% women) and isotretinoin (100% women) than men. In contrast, there was no notable difference by sex in the potency of topical corticosteroid agents prescribed.. For mild disease treated with topical agents alone, there is no notable difference in the treatment of men and women. Men are more likely than women to receive intensive treatments for severe psoriasis, at least in part because of the teratogenic potential of these treatments. There is a need for development of new treatments for severe psoriasis that are safe for women of childbearing potential.

Topics: Abnormalities, Drug-Induced; Administration, Topical; Anti-Inflammatory Agents; Dermatologic Agents; Drug Utilization; Etretinate; Female; Glucocorticoids; Humans; Isotretinoin; Male; Methotrexate; Middle Aged; Psoriasis; PUVA Therapy; Sex Factors

Topics: Adult; Drug Therapy, Combination; Female; Humans; Isotretinoin; Keratolytic Agents; Psoriasis; PUVA Therapy

Impetigo herpetiformis (IH) is a rare pustular dermatosis with unknown aetiology, typically occurring during pregnancy. Based upon a similar clinical and histological presentation, i.e. spongiform accumulation of polymorphonuclear leucocytes in the stratum corneum, several authors consider IH as a variant of generalized pustular psoriasis (GPP), while others state that IH is a separate entity. Skin-derived antileucoproteinase (SKALP) is a strong and specific inhibitor of human leucocyte elastase (HLE) and proteinase 3, two neutral proteinases that have been implicated in leucocyte migration and tissue destruction. Previously, we reported decreased SKALP activity in pustular forms of psoriasis compared with plaque psoriasis. In this study we present a case study of a patient with IH, where SKALP activity was measured using biochemical and immunochemical techniques. Epidermal scales and sera were collected during the course of the disease. Comparison was made with three patients with GPP and six patients with plaque psoriasis. Initially, anti-HLE activity in epidermal scales of the patient with IH was comparable with values in patients with GPP, i.e. decreased compared with plaque psoriasis. During the course of the disease, anti-elastase activity dropped to undetectable levels, concomitant with the appearance of free elastase activity. This finding suggests a total saturation of epidermal anti-HLE activity. Low levels of SKALP, presumably complexed with HLE, could be measured immunochemically in scale extracts. Serum levels of total SKALP correlated with the disease activity. We suggest that a reduced amount of epidermal SKALP contributes to an imbalance between elastase and its inhibitor, resulting in the formation of epidermal pustules. This mechanism of pustule formation could apply both to GPP and IH, suggesting a final common pathway in the pathogenic mechanisms of IH and GPP.

Topics: Adult; Enzyme-Linked Immunosorbent Assay; Epidermis; Female; Humans; Impetigo; Isotretinoin; Keratolytic Agents; Pregnancy; Pregnancy Complications; Pregnancy Trimester, Third; Proteinase Inhibitory Proteins, Secretory; Proteins; Psoriasis; Serine Proteinase Inhibitors

Topics: Acne Vulgaris; Etretinate; Humans; Isotretinoin; Psoriasis

Following the observation of increased trough whole blood cyclosporin A (CyA) concentrations and reduced renal function in a patient with recalcitrant generalized pustular psoriasis treated with a combination of CyA and etretinate, the effect of vitamin A analogues on human microsomal cytochrome P450-dependent CyA metabolism was investigated in vitro. In addition, the effect of terbinafine, a new allylamine antifungal agent, was also tested. Etretinate, its major metabolite acitretin, and isotretinoin, each at a single concentration of 100 microM, inhibited total hepatic microsomal CyA metabolism to a similar extent (33-45%, compared with control values). The generation of total primary and total secondary CyA metabolites was also inhibited to a similar extent by each of the retinoids. Conversely, terbinafine was without significant effect on CyA metabolism in vitro. The results, which suggest that inhibition of hepatic CyA metabolism by retinoids may contribute to increased circulating CyA concentrations, are discussed in relation to other potential drug interactions, and to the use of etretinate in reducing the CyA administered dose.

Topics: Acitretin; Aged; Antifungal Agents; Cyclosporine; Drug Therapy, Combination; Etretinate; Female; Humans; In Vitro Techniques; Isotretinoin; Male; Microsomes, Liver; Middle Aged; Naphthalenes; Psoriasis; Retinoids; Terbinafine

Topics: Abnormalities, Drug-Induced; Acne Vulgaris; Adolescent; Adult; Contraindications; Etretinate; Female; Humans; Isotretinoin; Pregnancy; Psoriasis

Administration of etretinate in a 29-year-old female patient suffering from severe pustular psoriasis caused a dramatic increase in liver enzymes. Liver biopsy revealed changes characteristic for drug-induced hepatitis. After normalization of liver parameters following withdrawal of etretinate, isotretinoin was administered during a severe pustular relapse. In contrast to etretinate, isotretinoin was well tolerated and resulted in a good therapeutic response. Thus, isotretinoin can be considered as an effective and safe therapeutic alternative for pustular psoriasis even after the occurrence of etretinate-induced hepatitis.

Topics: Adult; Chemical and Drug Induced Liver Injury; Etretinate; Female; Humans; Isotretinoin; Liver Function Tests; Psoriasis

The synthesis of new 10-acylderivatives of dithranol 1 is described. Compound 1 was reacted with the acid chlorides of all-trans retinoic acid 5, 13-cis-retinoic acid 6 and all-trans-9-(4-methoxy-2,3,6-trimethylphenyl)-3,7-dimethyl-nona-2,4,6,8- tetraenoate 7 in toluene and collidin as a base to give the coupling products 2, 3 and 4. The different structures were confirmed by high resolution 1H- and 13C-NMR spectroscopy. Initial investigations with the enzyme glucose-6-phosphate dehydrogenase indicate that all of them are inhibitors of the protein and therefore might have antipsoriatic activity.

Topics: Acitretin; Anthralin; Isotretinoin; Magnetic Resonance Spectroscopy; Psoriasis; Tretinoin

Possible early side-effects of retinoid treatment on bones were studied with the aid of bone-scintigraphy. Isotretinoin treatment (1.0 mg/kg daily for 4 months) was given to 18 patients with acne. Fifteen patients with psoriasis received etretinate treatment (0.7-1.0 mg/kg/day) for 4 months. In the group treated with isotretinoin, pathological uptake of radiolabel was found in three cases, while in the group treated with etretinate, no bone changes attributable to treatment were found. During isotretinoin treatment, a decrease in growth-plate activity was observed. Bone-scintigraphy is considered to be a suitable method for early screening for bone changes occurring in retinoid treatment.

Topics: Acne Vulgaris; Adolescent; Adult; Bone and Bones; Calcium; Etretinate; Growth Plate; Humans; Isotretinoin; Male; Phosphorus; Prospective Studies; Psoriasis; Radionuclide Imaging; Sacroiliac Joint

Skeletal effects of retinoids on the spine were studied in two clinical trials. In the first study, spinal radiographs of 96 patients who had been treated with isotretinoin for 4 to 9 months were reviewed. The average age of these patients was 25 years, and during treatment or within 2 1/2 years after the end of treatment, 26% of the patients showed progressive formation of small bony spurs consisting of tiny horizontal excrescences that arose at the anterior margin of one or more vertebral bodies adjacent to the intervertebral disk. In a second study, the radiographs of 241 patients with psoriasis who were treated continually for 1 to 2 years with acitretin were examined. Many of these patients had abnormal radiographs at the start of therapy. These preexisting conditions included psoriatic arthritis, degenerative arthritis, and diffuse idiopathic skeletal hyperostosis. Five percent of the patients showed progression of their abnormalities during the study. The difference in the rate of spur formation in the two groups may be due to multiple factors and not simply to retinoid therapy. Because of the extensive amount of preexisting disease in the psoriasis group compared with the relatively normal appearance of the spine in the isotretinoin group, the underlying disease process may be more important than the retinoid therapy. The development of the spinal spurs was not associated with specific clinical symptoms. Since there was no control group, it is unknown whether the spurs would have developed or progressed in the absence of retinoid therapy.

Topics: Acitretin; Adult; Humans; Isotretinoin; Psoriasis; Spinal Diseases; Time Factors; Tretinoin

The present investigation focused on the oxidative response of polymorphonuclear neutrophil leukocytes in psoriasis, in particular pustular psoriasis and how this response was affected by different retinoid compounds. In the active phase of pustular psoriasis, the neutrophil chemiluminescence response to the chemotactic peptide f-met-leu-phe and to phorbol myristate acetate was enhanced and correlated to the development of pustules, whereas cells from psoriasis vulgaris patients showed normal chemiluminescence response. Retinoids, particularly tretinoin (= retinoic acid) and isotretinoin caused a pronounced inhibition of the chemiluminescence response only in primed neutrophils in vivo and in vitro, whereas etretinate and the metabolite Ro 10-1670 was less inhibitory. Retinoic acid furthermore inhibited the Fc-mediated phagocytosis, but did not affect C3bi-mediated phagocytosis. These data suggest that the antiinflammatory effect of retinoids may operate by affecting neutrophil activation and function.

Topics: Acitretin; Dermatologic Agents; Etretinate; Female; Humans; In Vitro Techniques; Isotretinoin; Luminescent Measurements; Middle Aged; N-Formylmethionine Leucyl-Phenylalanine; Neutrophils; Phagocytosis; Psoriasis; Retinoids; Tetradecanoylphorbol Acetate; Tretinoin

Treatment with retinoids results in increased serum triglyceride and cholesterol and reduced HDL-cholesterol; dietary supplementation with fish oil lowers serum lipids. Therefore combining retinoids with fish oil may reduce retinoid hyperlipidaemia. Increased triglyceride due to isotretinoin was reduced by 70% (P less than 0.05) and cholesterol by 45% (P less than 0.05) after addition of fish oil; placebo oil had no effect. These decreases were not associated with changes in levels of HDL-cholesterol or reduction of increased levels of apoprotein B. Increased triglyceride due to etretinate was reversed after the addition of fish oil (P less than 0.01), but cholesterol levels did not change. Therefore fish oil inhibits hypertriglyceridaemia due to isotretinoin and etretinate and reduces increased cholesterol levels due to isotretinoin; this effect is likely to be due to altered lipoprotein composition.

Topics: Acne Vulgaris; Adolescent; Adult; Aged; Cholesterol; Etretinate; Female; Fish Oils; Humans; Hyperlipidemias; Isotretinoin; Male; Middle Aged; Psoriasis; Tretinoin; Triglycerides

The effects of four retinoids, all-trans-retinoic acid (tretinoin), 13-cis-retinoic acid (isotretinoin), R0 10-1670 (etretin) and the arotinoid, R0 15-0778, on fibroblast proliferation and glycosaminoglycans (GAG) secretion in vitro were studied. Fibroblasts lines cultured from normal skin (HSF) were compared with those from lesional (PSA) and non-lesional (PSB) psoriatic skin. In general, the retinoids inhibited proliferation; the action was cytostatic, in rank order tretinoin greater than isotretinoin greater than etretin greater than arotinoid. The psoriatic cells tended to be more sensitive than the HSF lines, overall mean proliferation values (+/- SEM), as a percentage of untreated controls being: HSF 72 ++- 3, PSA 61 +/- 3 and PSB 54 +/- 3. Stimulation of GAG secretion at low concentrations (10(-7) M) of all four retinoids, declined as concentrations increased, and secretion was inhibited at 10(-4)M in PSB fibroblasts. Calculation of effects on GAG secretion due to changes in cell density confirmed the rank order for direct stimulation of secretion as arotinoid greater than etretin greater than isotretinoin greater than tretinoin. Electrophoresis of [3H]-labelled glycosaminoglycans secreted in the presence of 10(-7) M arotinoid showed that it was predominantly hyaluronic acid, as in untreated cells. These data confirm that different retinoids have contrasting levels of effects on mesenchymal cells and suggest a greater sensitivity to drugs in fibroblasts from psoriatic skin.

Topics: Acitretin; Cell Division; Cell Line; Fibroblasts; Glycosaminoglycans; Humans; Isotretinoin; Psoriasis; Retinoids; Skin; Tretinoin

Retinoids are natural and synthetic analogues of vitamin A. They have a marked influence on the differentiation of epithelial tissues by modifying membrane glycoconjugates and by acting through cytosolic and nuclear mechanisms like steroid hormones. Their clinical and biological toxic effects are numerous, but they are usually benign and reversible. However the possibility of teratogenic effects requires close monitoring of female patients. Etretinate is particularly effective in disorders of keratinisation (psoriasis, ichthyosis) whereas isotretinoin is the best known therapy of severe acne. Moreover the possible role of retinoids in the prevention and treatment of certain cancers gives hopeful prospects.

Topics: Acne Vulgaris; Chemical Phenomena; Chemistry; Etretinate; Humans; Ichthyosis; Isotretinoin; Neoplasms; Psoriasis; PUVA Therapy; Recurrence; Retinoids; Tretinoin

Isotretinoin, a synthetic retinoid that has been prescribed for over 500,000 patients with cystic acne, has been associated with both spinal hyperostosis and a disorder similar to diffuse idiopathic skeletal hyperostosis. We describe a syndrome of tendon and ligament calcification, primarily in extraspinal locations, that we have observed after long-term therapy for psoriasis and disorders of keratinization with etretinate, another synthetic retinoid. Of 38 patients who had received etretinate (average dose, 0.8 mg per kilogram of body weight per day; average duration, 60 months), 32 (84 percent) had radiographic evidence of extraspinal tendon and ligament calcification. The most common sites of involvement were the ankles (29 patients [76 percent]), pelvis (20 patients [53 percent]), and knees (16 patients [42 percent]); spine involvement was uncommon in this group of etretinate-treated patients. Involvement tended to be bilateral and multifocal. Fifteen (47 percent) of the 32 affected patients had no bone or joint symptoms at the sites of radiographic abnormality. Thus, tendon and ligament calcification can occur without vertebral involvement as well as in association with it (for example, as part of the spectrum of diffuse idiopathic skeletal hyperostosis). We have identified extraspinal tendon and ligament calcification as a toxic effect that is commonly associated with long-term etretinate therapy.

Topics: Adult; Aged; Calcinosis; Etretinate; Female; Humans; Isotretinoin; Knee Joint; Ligaments; Lupus Erythematosus, Systemic; Male; Middle Aged; Pelvis; Prospective Studies; Psoriasis; Radiography; Skin Diseases; Spinal Diseases; Tendons; Tretinoin

A 64-year-old woman developed biopsy-proven hepatitis during oral treatment of severe pustular psoriasis of palms and soles with an aromatic retinoid, etretinate. The elevations in hepatic enzyme levels reappeared when etretinate was reinstituted 18 months later. Analysis of serum and subcutis showed normal therapeutic concentrations of the drug. Isotretinoin therapy, although apparently devoid of hepatotoxicity, was clinically only marginally effective. Evidence compiled from the literature suggests that etretinate-hepatitis is a drug-specific reaction.

Topics: Chemical and Drug Induced Liver Injury; Etretinate; Female; Humans; Isotretinoin; Middle Aged; Psoriasis; Tretinoin

Topics: Etretinate; Humans; Isotretinoin; Psoriasis; PUVA Therapy; Retinoids; Skin Diseases; Tretinoin

The clinical response to isotretinoin (13-cis-retinoic acid) in 11 patients with generalized pustular psoriasis was evaluated. Control of pustulation and systemic symptoms was achieved in ten cases, but additional therapy was required to produce complete clearing of all psoriatic lesions. Also, the efficacy of isotretinoin and etretinate in the treatment of chronic plaque psoriasis was compared in 29 patients. Isotretinoin was found to be less effective than etretinate in the treatment of chronic plaque psoriasis.

Topics: Adult; Aged; Biopsy; Chronic Disease; Etretinate; Female; Humans; Isotretinoin; Male; Middle Aged; Psoriasis; Tretinoin

Topics: Adult; Aged; Female; Humans; Isotretinoin; Male; Middle Aged; Psoriasis; Tretinoin

Topics: Acne Vulgaris; Humans; Isotretinoin; Psoriasis; Tretinoin

In our clinical trials of isotretinoin therapy for cystic acne and etretinate treatment of psoriasis, eight patients had growth of excessive granulation tissue. The granulation tissue was found in resolving acne lesions in one patient taking isotretinoin. Among the psoriatic patients taking etretinate, the granulation tissue usually was seen adjacent to nail plates. In two patients, the side effect caused them to stop retinoid therapy. The tissue response did not appear to be related to the daily or cumulative retinoid dose.

Topics: Acne Vulgaris; Adolescent; Adult; Aged; Granulation Tissue; Granuloma; Humans; Isotretinoin; Male; Middle Aged; Psoriasis; Skin Diseases; Tretinoin

The naturally occurring retinoids (vitamin A alcohol = retinol and all-trans-retinoic acid) have been largely replaced by synthetic retinoids in recent years as systemic drugs for use in dermatology. At the present time, two synthetic retinoids are commercially available: etretinate (Tigason) and isotretinoin (Accutane). These compounds-which have a more favourable therapeutic index than the naturally occurring retinoids-ushered in a new era of dermatological therapy by their potent antikeratinizing, antiseborrhoeic (only isotretinoin) and antineoplastic action. The broadest indications for the use of these retinoids are psoriasis (etretinate) and cystic acne (isotretinoin), whereas the most dramatic effects are encountered in a number of severe ichthyosiform disorders. Another important, although at present not clearly defined role of the retinoids is in the prophylaxis of skin tumours.

Topics: Acne Vulgaris; Etretinate; Humans; Ichthyosis; Isotretinoin; Psoriasis; Retinoids; Skin Diseases; Skin Neoplasms; Tretinoin

Topics: Etretinate; Humans; Isotretinoin; Keratosis; Psoriasis; Skin; Skin Diseases; Tretinoin

Topics: Acne Vulgaris; Humans; Isotretinoin; Keratins; Psoriasis; Skin Diseases; Skin Neoplasms; Tretinoin; Vitamin A

Retinoids possess regulatory influences on growth and differentiation of epithelial tissues. They induce a population of keratinozytes with normal pattern of differentiation, they have antiproliferative properties, and they show antineoplastic effects by inhibition of malignant transformation of cells in vitro. Also the dermis undergoes distinct alterations under oral administration of retinoids. By stimulating T-lymphocytes and by inhibition of neutrophil migration retinoids seem to develop immunmodulating and antiinflammatory effects. The aromatic retinoid Etretinate is therapeutically used in severe forms of psoriasis and in various genodermatoses with disorders of keratinization as for example ichthyosis, dyskeratosis follicularis Darier, and pityriasis rubra pilaris.

Topics: Acne Vulgaris; Administration, Oral; Etretinate; Humans; Isomerism; Isotretinoin; Psoriasis; Rosacea; Skin Diseases; Tretinoin

Topics: Acne Vulgaris; Animals; Cocarcinogenesis; Etretinate; Humans; Immunity; Isomerism; Isotretinoin; Keratosis; Polyamines; Psoriasis; Skin; Skin Diseases; Teratogens; Tretinoin; Triglycerides; Vitamin A