acyclovir and Headache

Acute hemicerebellitis, marked by headache with or without cerebellar signs, is a rare clinical entity involving a unilateral cerebellar hemisphere. The pathogenesis of acute hemicerebellitis remains unclear, and the disease rarely occurs in adults. Here, we report an 18-year-old woman who presented with a lack of coordination of the right hand and leg lasting longer than one week, following a pulsatile headache. A neurological examination disclosed ocular dysmetria, right-sided limb ataxia and slight truncal ataxia. Cerebrospinal fluid analysis showed mononuclear pleocytosis. The serology and autoimmune studies were unremarkable. Brain magnetic resonance imaging (MRI) revealed a focal signal change in the right cerebellar hemisphere and vermis. Acute hemicerebellitis was diagnosed, and the patient was treated with intravenous methylprednisolone sodium succinate and acyclovir. Subsequently, the headache resolved, and the cerebellar signs were markedly improved. Twenty days after admission, she became asymptomatic and brain MRI showed resolution of cerebellar hyperintensity on the right side. In conclusion, we identified only 6 additional patients with adult-onset acute hemicerebellitis from previous reports, highlighting the importance of recognizing this rare clinical entity. Its clinical outcome is usually favorable, but in the acute phase, attention should be directed toward clinical symptoms that are suggestive of increased intracranial pressure.

Topics: Acute Disease; Acyclovir; Adolescent; Adult; Age of Onset; Antiviral Agents; Cerebellar Diseases; Encephalitis, Viral; Female; Glucocorticoids; Headache; Humans; Intracranial Hypertension; Magnetic Resonance Imaging; Methylprednisolone Hemisuccinate; Treatment Outcome

Genital herpes is prevalent and sometimes debilitating. Likewise, herpes zoster ('shingles') can be painful and often disabling. The treatment of these conditions has been advanced over the past two decades by the introduction of guanosine nucleoside antivirals such as valacyclovir (Valtrex), Glaxo Wellcome), the highly bioavailable prodrug of acyclovir (Zovirax), Glaxo Wellcome). This review describes the pharmacology, pharmacokinetics, clinical efficacy and tolerability of valacyclovir and considers its clinical attributes in the context of those of the antivirals, acyclovir and famciclovir (Famvir), SmithKline Beecham). The data demonstrate that valacyclovir is more effective than placebo and as effective as other antivirals in the episodic and suppressive treatment of recurrent genital herpes. Valacyclovir is the only antiviral shown to be effective with a short (3-day) course in the episodic treatment of recurrent genital herpes, as well as with once-daily dosing for daily suppressive therapy. In herpes zoster, valacyclovir is as effective as famciclovir and more effective than either placebo or acyclovir at facilitating cutaneous healing and healing of zoster-associated pain and post-herpetic neuralgia. Valacyclovir is well tolerated, with convenient dosing frequencies for the treatment of genital herpes or herpes zoster, it also has the option for use as a short course therapy in the episodic treatment of recurrent genital herpes, all of which are important benefits in the management of these conditions.

Topics: Acyclovir; Antiviral Agents; Clinical Trials as Topic; Headache; Herpes Genitalis; Herpes Zoster; Humans; Nausea; Secondary Prevention; Tissue Distribution; Treatment Outcome; Valacyclovir; Valine

Topics: Acyclovir; Adrenal Cortex Hormones; Adult; Baclofen; Calcium Channel Blockers; Carbamazepine; Cervical Vertebrae; Cluster Headache; Drug Therapy, Combination; Ergotamine; Eye Diseases; Facial Pain; Female; Giant Cell Arteritis; Headache; Humans; Lithium; Male; Methysergide; Middle Aged; Osteoarthritis; Otorhinolaryngologic Diseases; Psychotherapy; Psychotropic Drugs; Temporomandibular Joint Dysfunction Syndrome; Trigeminal Neuralgia; Vidarabine

Oral valacyclovir's efficacy and tolerability as suppressive therapy versus episodic therapy were compared for recurrent herpes labialis (RHL). Subjects with a history of at least 3 RHL episodes in the past year were randomized to receive 6 months of oral valacyclovir episodic therapy at the first sign of prodrome (two 2-g doses separated by 12 hours) and 6 months of oral valacyclovir suppressive therapy (1 g once daily) for 6 months in open-label, crossover fashion. The mean +/- SE number of recurrences per 120 days of follow-up (primary endpoint) was lower with suppressive therapy (0.30 +/- 0.41) than episodic therapy (0.71 +/- 0.79) (P < .005). The probability of remaining recurrence free over 6 months was significantly higher with suppressive therapy than episodic therapy. The median time to first recurrence was 81 days with episodic therapy and was not calculable (> 180 days) for suppressive therapy (P = 0.021). Data for secondary efficacy endpoints (pain severity score, mean duration of recurrences, maximal total lesion area) showed approximately a 30% to 50% reduction in mean values with suppressive therapy compared with episodic therapy, but results were statistically significantly different between the regimens for pain severity only. The percentage of subjects with at least one adverse event over 6 months of treatment that was considered to be drug related was 3% with suppressive therapy and 6% with episodic therapy. Suppressive therapy with oral valacyclovir was more effective than episodic therapy with oral valacyclovir in reducing the frequency of recurrences of herpes labialis and prolonging the time to first recurrence and was also similarly well-tolerated.

Topics: Acyclovir; Administration, Oral; Adult; Antiviral Agents; Cross-Over Studies; Drug Administration Schedule; Female; Headache; Herpes Labialis; Humans; Lip Diseases; Male; Middle Aged; Recurrence; Sinusitis; Time Factors; Treatment Outcome; Valacyclovir; Valine

Topics: 2-Aminopurine; Acyclovir; Aged; Antiviral Agents; Double-Blind Method; Famciclovir; Gastrointestinal Diseases; Headache; Herpes Zoster; Humans; Middle Aged; Nausea; Neuralgia; Pain; Prospective Studies; Time Factors; Treatment Outcome; Valacyclovir; Valine

131 patients with frequently recurring genital herpes were treated for 1 year with reducing doses of oral acyclovir. The time to first recurrence in patients who commenced therapy on 400 mg twice a day was statistically significantly shorter than those on 200 mg four times a day (p less than 0.02) and as the total daily dose and frequency of therapy were lowered so the time to first recurrence was shortened. By the end of 60 days on 200 mg once a day (the lowest daily dose) 56% of patients had recurrences. Patients showed a marked reduction in the frequency of recurrence during therapy (from a mean of 1.1 per 28 days before to 0.11 during treatment, p = 0.0001). After stopping treatment the frequency of recurrences (0.71 per 28 days) was significantly less than the pre-treatment period (p = 0.001). No important side-effects were seen. It is concluded that long-term suppression with acyclovir is safe and effective for patients with recurrent genital herpes.

Topics: Acyclovir; Administration, Oral; Adult; Bilirubin; Clinical Trials as Topic; Drug Administration Schedule; Female; Headache; Herpes Genitalis; Humans; Immunosuppression Therapy; Male; Patient Compliance; Random Allocation; Recurrence; Tablets; Time Factors

We identified an additional case of documented Rotavirus meningitis in an adult with full medical history. A previously healthy 37-year-old patient presented herself for transient aphasia associated with fever and headaches at the end of a one-week history of gastroenteritis. Cerebrospinal fluid (CSF) analysis revealed lymphocytic meningitis, and treatment with aciclovir was initiated. Rotavirus A reverse transcription-polymerase chain reaction (RT-PCR) was positive in CSF and the patient's stools in favor of Rotavirus meningitis. Testing for other viruses was negative. Magnetic resonance imaging (MRI) showed no signs of encephalitis. Aphasia was resolutive in less than 12 hours, and no neurological symptoms relapsed. All symptoms evolved favorably despite aciclovir discontinuation. Viral sequencing methods have recently identified unexpected viruses as potential causative agents in meningitis, including Rotavirus. We confirm the detectability of Rotavirus in the analysis of CSF in the context of Rotavirus gastroenteritis in an adult. This case suggests postviral headache and neurological deficits with cerebrospinal fluid lymphocytosis (HaNDL) syndrome may be linked to previously undetected direct viral infection of the central nervous system. Therefore, clinicians should consider Rotavirus meningitis in diagnosing meningitis associated with gastroenteritis in adults.

Topics: Acyclovir; Adult; Aphasia; Gastroenteritis; Headache; Humans; Meningitis; Rotavirus

Topics: Acute Disease; Acyclovir; Adrenal Cortex Hormones; Antiviral Agents; Cerebellar Ataxia; Cerebellar Diseases; Child; Consciousness Disorders; COVID-19; COVID-19 Drug Treatment; COVID-19 Nucleic Acid Testing; Drainage; Encephalitis, Viral; Headache; Humans; Hydrocephalus; Male; Nasopharynx; Neuroimaging; SARS-CoV-2

Development of neurological complications of varicella zoster virus reactivation is relatively uncommon, particularly in an immunocompetent child.. An 11-year-old Asian girl presented with headache and skin rash on her left chest. She was diagnosed with meningitis, and herpes zoster was confirmed by polymerase chain reaction using cerebrospinal fluid. Acyclovir was administered intravenously. Given the favorable evolution of the clinical course, she was discharged from the hospital on day 8 of her illness. She had no apparent sequelae or comorbidities at the time of the 6-week follow-up.. Neurological complications such as meningitis due to varicella zoster virus reactivation are uncommon, especially in an immunocompetent child; no specific immune deficiency was identified in our patient. We conclude that, although rare, varicella zoster virus should be recognized as a potential cause of viral meningitis in immunocompetent children.

Topics: Acyclovir; Administration, Intravenous; Antiviral Agents; Cerebrospinal Fluid; Child; Exanthema; Female; Headache; Herpes Zoster; Herpesvirus 3, Human; Humans; Immunocompetence; Meningitis, Viral; Treatment Outcome

Topics: Acyclovir; Adolescent; Diagnosis, Differential; Emergency Service, Hospital; Encephalitis, Varicella Zoster; Exanthema; Fever; Headache; Herpesvirus 3, Human; Humans; Infusions, Intravenous; Male; Neck Pain; Risk Assessment; Severity of Illness Index; Treatment Outcome

HaNDL (transient headache and neurological deficits with cerebrospinal fluid lymphocytosis) syndrome is an infrequent condition included at group 7 "headache attributed to non-vascular intracranial disorder" in the recent International Classification of Headache Disorders (ICHD-3), code 7.3.5. The description states "migraine-like headache episodes (typically 1-12) accompanied by neurological deficits including hemiparaesthesia, hemiparesis and/or dysphasia, but positive visual symptoms only uncommonly, lasting several hours. There is lymphocytic pleocytosis. The disorder resolves spontaneously within 3 months". In this description confusional state is not considered as a main symptom, even if in the literature this aspect is frequently reported. Here, we report the cases of two young boys presenting with confusional state as the main complaint. The possible pathogenesis of the different clinical presentation is discussed.

Topics: Acyclovir; Adolescent; Ceftriaxone; Confusion; Headache; Humans; Lymphocytosis; Male; Nervous System Diseases; Young Adult

Viral encephalitis are rare and potentially serious conditions with different etiologist, and not always identifiable. Our aim is to describe the etiological, clinical presentation and neurological outcome of viral encephalitis admitted in Paediatrics Intensive Care Units (PICUs) in Spain.. Observational prospective multicenter study. Children with viral encephalitis admitted to 14 PICUs, for a period of 3 years (2010-2013) were included. Polymerase chain reaction for the etiological diagnosis and neurotropic virus serology in blood and cerebrospinal fluid were used. Personal history, clinical presentation, evolution and neurological status at discharge were recorded.. 80 patients were included with a mean age of 5 years, 70% male. The most relevant clinical symptoms were decreased consciousness (86%), fever (82.4%), seizures (67%), vomiting (42%), headache (27%), agitation (25%) and dis-orientation (23%). The etiologic diagnosis was established in 35%, being more frequent herpes simplex virus and enterovirus. The outcome was discharge without sequelae in 55 patients (69%), mild to moderate sequelae in 19 (23.5%) and severe in 6 (7.5%). Two patients died.. In the Spanish PICU etiological diagnosis was established only in a third of cases of children with suspected acute viral encephalitis. Despite the clinical severity we observed a low mortality and morbidity rate. At discharge from the PICU, most children had no neurological sequelae or were mild.. Etiologia, presentacion clinica y evolucion neurologica de las encefalitis viricas graves en la edad pediatrica (estudio ECOVE).. Introduccion. Las encefalitis viricas son procesos raros y potencialmente graves, con etiologia diversa y no siempre identificable. El objetivo es describir las caracteristicas etiologicas, la presentacion clinica y la evolucion neurologica de las encefalitis viricas que ingresaron en las unidades de cuidados intensivos pediatricos (UCIP) en España. Pacientes y metodos. Estudio prospectivo multicentrico observacional. Se incluyeron los niños ingresados en 14 UCIP con diagnostico de encefalitis virica durante un periodo de tres años (2010-2013). Para el diagnostico etiologico se utilizo reaccion en cadena de la polimerasa y serologia a virus neurotropos en la sangre y el liquido cefalorraquideo. Se registraron los antecedentes personales, la presentacion clinica, la evolucion y la situacion neurologica en el momento del alta. Resultados. Se incluyeron 80 pacientes con edad media de 5 años; el 70%, varones. Los sintomas clinicos mas relevantes fueron disminucion de conciencia (86%), fiebre (82,4%), convulsiones (67%), vomitos (42%), cefalea (27%), agitacion (25%) y desorientacion (23%). Se llego al diagnostico etiologico en un 35%, y los mas frecuentes fueron virus herpes simple y enterovirus. La evolucion fue curacion sin secuelas en 55 pacientes (69%, sobre todo enterovirus, rotavirus y virus respiratorios), secuelas leves-moderadas en 19 (23,5%) y graves en seis (7,5%). Dos pacientes fallecieron. Conclusiones. En las UCIP españolas solo se realizo el diagnostico etiologico en un tercio de los niños con sospecha de encefalitis virica grave. A pesar de la gravedad clinica, hemos observado una tasa de mortalidad y morbilidad baja. La amplia mayoria son dados de alta de la UCIP con ninguna o escasa secuela neurologica.

Topics: Acute Disease; Acyclovir; Adolescent; Antiviral Agents; Brain Damage, Chronic; Child; Child, Preschool; Clarithromycin; Consciousness Disorders; Encephalitis, Viral; Female; Fever; Headache; Humans; Infant; Male; Prospective Studies; Seasons; Seizures; Serologic Tests; Spain; Treatment Outcome; Vomiting

We present a patient with polymorphic ventricular tachycardia and subsequent ventricular fibrillation with acquired long QT syndrome secondary to herpes encephalitis.

Topics: Acute Disease; Acyclovir; Antiviral Agents; Defibrillators, Implantable; Electrocardiography; Encephalitis, Herpes Simplex; Female; Foscarnet; Ganciclovir; Headache; Heart Arrest; Herpesvirus 2, Human; Humans; Long QT Syndrome; Magnetic Resonance Imaging; Meningitis, Viral; Middle Aged; Seizures; Tachycardia, Ventricular; Torsades de Pointes

Topics: Acyclovir; Antibodies, Viral; Antiviral Agents; DNA, Viral; Encephalitis, Varicella Zoster; Female; Headache; Herpesvirus 3, Human; Humans; Hypesthesia; Immunoglobulin G; Middle Aged; Skin

Here, we demonstrate a first case of tick-borne encephalitis (TBE) associated with an isolated reversible splenial corpus callosum lesion (IRSL) and highlight the wide range of different clinical entities in which such alterations have been observed. A 42-year-old man showed fever, cephalgia and mild disturbance of coordination and gait. Diagnosis was ascertained by slight CSF-pleiocytosis and positive TBE-IgG as well as by positive intrathekal specific antibody index on follow-up. MRI demonstrated a single ovoid hyperintensity in T2 and DWI with reduction in ADC in the splenium of corpus callosum which was abrogated in follow-up after 6 weeks. Most entities of IRSL presented with excellent prognosis, including our novel case of TBE. We discuss different possible pathomechanisms and the so far unexplained propensity of the splenium for such alterations. Clinicians should be familiar with this phenomenon to avoid unnecessary diagnostic or therapeutic efforts.

Topics: Acyclovir; Adult; Anti-Bacterial Agents; Antiviral Agents; Ataxia; Ceftriaxone; Corpus Callosum; Diffusion Magnetic Resonance Imaging; Encephalitis, Tick-Borne; Fever; Gait Disorders, Neurologic; Headache; Humans; Image Processing, Computer-Assisted; Immunoglobulin G; Magnetic Resonance Imaging; Male; Neck Pain

Varicella zoster virus (VZV) belongs to the group of herpes viruses. It can cause a number of nervous system infections. We present 2 of 4 patients seen recently suffering from acute meningoencephalitis, in which VZV proved to be the infectious agent. The first patient was a 57-year-old woman with headache, vomiting, and sudden aggressiveness. The second patient was a 60-year-old man with headache, nausea, and vomiting. Neither patient had skin eruptions usually associated with VZV reactivation, nor had either recently suffered from herpes zoster. Both patients had in their cerebrospinal fluid a lymphocytic pleocytosis, a decreased glucose concentration and and an elevated protein concentration. The patients recovered within a few days of starting intravenous treatment with aciclovir 10 mg/kg 3 times daily for one week. Recent literature shows that VZV is a common pathogen in meningoencephalitis and is probably underestimated as a putative cause of this condition. VZV meningoencephalitis usually has a mild course, but serious complications have been reported. Patients present with headache and usually fever. Nuchal rigidity and meningeal irritation are not always present. Since the advent of the PCR technique, VZV has been readily demonstrable. Anti-viral treatment is advised despite the lack of placebo-controlled studies, and may be combined with prednisone.

Topics: Acyclovir; Antiviral Agents; Encephalitis, Varicella Zoster; Female; Headache; Herpesvirus 3, Human; Humans; Male; Meningoencephalitis; Middle Aged; Polymerase Chain Reaction

Topics: Acyclovir; Antiviral Agents; Encephalitis, Herpes Simplex; Female; Headache; Herpesvirus 1, Human; Humans; Middle Aged; Photophobia

Bilateral facial nerve paralysis is an uncommon presentation and even more so in children. There are reports of different causes of bilateral facial nerve palsy. It is well-established that hypertension and chickenpox causes unilateral facial paralysis and the importance of checking the blood pressure in children with facial nerve paralysis cannot be stressed enough. The authors report a boy with bilateral facial nerve paralysis in association with hypertension and having recently recovered from chickenpox. The authors review aspects of bilateral facial nerve paralysis as well as hypertension and chickenpox causing facial nerve paralysis.

Topics: Acyclovir; Antihypertensive Agents; Antiviral Agents; Chickenpox; Child; Cooperative Behavior; Diagnosis, Differential; Facial Paralysis; Follow-Up Studies; Headache; Humans; Hypertension, Renal; Interdisciplinary Communication; Losartan; Male; Neurologic Examination; Valacyclovir; Valine

Ramsay-Hunt syndrome, herpes zoster oticus (HZO), derived its name from James Ramsay Hunt, who first described it in 1907. It is classically characterized by acute peripheral facial paralysis, herpetic eruptions on the auricle, and vestibulocochlear dysfunction due to the reactivation of varicella zoster virus (VZV). In this Case Report, the authors describe an HZO patient with simultaneous VZV encephalitis. To date, only eight cases of HZO associated with VZV encephalitis have been reported in the English literature. Therefore, the authors discuss all the aspects of this rare entity, including clinical examination, radiological evaluation, laboratory evaluation, and treatment options.

Topics: Acyclovir; Adult; Dextrans; Drug Administration Schedule; Drug Therapy, Combination; Earache; Encephalitis, Varicella Zoster; Facial Hemiatrophy; Headache; Herpes Zoster Oticus; Humans; Male; Tinnitus

We report varicella-zoster virus (VZV) meningitis in a healthy adult woman with no antecedent rash and with hypoglycorrhachia. Cerebrospinal fluid (CSF) examination revealed the presence of VZV DNA, anti-VZV immunoglobulin G (IgG) antibody, and intrathecal production of anti-VZV IgG antibody.

Topics: Acyclovir; Adult; Antiviral Agents; DNA, Viral; Exanthema; Female; Glucose; Headache; Herpesvirus 3, Human; Humans; Immunocompetence; Meningitis, Viral

Topics: Acyclovir; Anti-Bacterial Agents; Antiviral Agents; Aspirin; Diagnosis, Differential; Female; Headache; Humans; Meningitis, Viral; Middle Aged; Photophobia; Recurrence; Spinal Puncture; Valacyclovir; Valine

Topics: Acyclovir; Adult; Anticoagulants; Antiviral Agents; CD4 Lymphocyte Count; Encephalitis, Herpes Simplex; Headache; Heparin; Herpes Zoster Oticus; HIV Infections; HIV-1; Humans; Male; Radiography; Sinus Thrombosis, Intracranial; Thrombophilia; Viral Load

Topics: Acyclovir; Adult; Antigens, Viral; Brain; Cerebral Arteries; DNA, Viral; Early Diagnosis; Encephalitis, Herpes Simplex; Female; Frontal Lobe; Headache; Herpesvirus 1, Human; Humans; Magnetic Resonance Imaging; Meninges; Neurons; Seizures; Temporal Lobe; Tomography, X-Ray Computed; Treatment Outcome

We present the case of a 38-yr-old woman who required an epidural blood patch in the context of acute varicella (chickenpox). The unique risks in this case include the possible triggering of central nervous system complications after the introduction of viremic blood into the epidural or intrathecal space. However, the risk was believed to be acceptable because the patient was receiving antiviral coverage. She enjoyed complete relief of her headache but experienced transient back and leg pain. Leptomeningeal irritation caused by acute varicella infection may put patients at increased risk for pain after epidural blood patch.

Topics: Acute Disease; Acyclovir; Adult; Antiviral Agents; Blood Patch, Epidural; Chickenpox; Female; Headache; Humans; Magnetic Resonance Imaging; Pain; Spinal Cord; Valacyclovir; Valine

Topics: Acute Disease; Acyclovir; Aged; Anticonvulsants; Antiviral Agents; Carbamazepine; Diagnosis, Differential; Female; Headache; Herpes Zoster; Humans; Oxcarbazepine; Time Factors; Trigeminal Neuralgia; Valacyclovir; Valine

Topics: Acyclovir; Adolescent; Antiviral Agents; Diagnosis, Differential; Electroencephalography; Encephalitis, Varicella Zoster; Fever; Headache; Herpes Zoster; Humans; Male; Migraine Disorders; Photophobia; Vomiting

Topics: Acyclovir; Digestive System; Exanthema; Headache; Herpes Labialis; Humans; Randomized Controlled Trials as Topic; Valacyclovir; Valine

A previously healthy 26-year-old man complained of gradually increasing headache after an attack of flu. After 4 days an erythema with papules but no blisters was noted in the area of distribution of the left 10th thoracic nerve. As a child he had varicella (chickenpox) without complications.. Lymphocytic pleocytosis and evidence of an abnormal blood-brain barrier were noted in cerebrospinal fluid (CSF). Serology for varicella zoster virus revealed an IgG titre of > 7400 IU/l in serum and 21 IU/l in CSF. The corresponding IgM titres were negative.. The headaches and cutaneous changes regressed under i.v. treatment with acyclovir, 10 mg/kg body weight, 3 x daily for 10 days. Repeat CSF examination after 10 days showed merely minimal residual changes of inflammation.. This case illustrates the risk of severe neurological complications of herpes zoster infection. A seemingly minor rash with headache must be correctly diagnosed and immediate high-dosage acyclovir treatment instituted to prevent life-threatening and severe complications of herpes zoster meningitis or encephalitis.

Topics: Acyclovir; Adult; Antibodies, Viral; Antiviral Agents; Cerebrospinal Fluid; Erythema; Headache; Herpes Zoster; Herpesvirus 3, Human; Humans; Immunoglobulin G; Male; Meningitis, Viral; Thoracic Nerves

Topics: Acyclovir; Female; Headache; Herpes Simplex; Humans; Middle Aged; Recurrence

Topics: Acyclovir; Anti-Bacterial Agents; Antihypertensive Agents; Diagnosis, Differential; Headache; Humans; Magnetic Resonance Imaging; Prednisolone; Tomography, X-Ray Computed

Overall, acyclovir is a remarkably safe drug considering its potent antiviral effect. The most frequent reactions with short-term use of oral acyclovir are nausea and vomiting and with 6 months' use headache, diarrhea, nausea, and vomiting. These symptoms are also seen frequently with placebos. The most frequent adverse reaction to intravenous use has been inflammation and phlebitis at the injection site. The two most important serious adverse effects are (1) encephalopathic changes with abnormal electroencephalograms and lethargy, tremors, confusion, and seizures and (2) renal precipitation of the drug because of a rapid bolus of drug administered parenterally. Safety of acyclovir for use during pregnancy and in neonates and young children has not been established.

Topics: Acyclovir; Administration, Oral; Administration, Topical; Animals; Chemical Precipitation; Diarrhea; Female; Headache; Humans; Injections, Intravenous; Kidney; Nausea; Pregnancy; Vomiting