beta-carotene and Abnormalities--Drug-Induced

Vitamin A has the unique distinction of being readily available over the counter, yet conferring significant toxic and teratogenic potential. Although vitamin A deficiency is relatively rare in the United States, globally it is the most common cause of blindness. The following is a review of the various forms and derivatives of vitamin A and their associations with potential adverse perinatal outcomes.. Obstetricians & Gynecologists, Family Physicians.. After participating in this CME activity, physicians should be better able to identify sources of Vitamin A, distinguish between toxic and non toxic forms of Vitamin A and counsel patients regarding the dosages of Vitamin A that are tolerable during pregnancy.

Topics: Abnormalities, Drug-Induced; beta Carotene; Clinical Trials as Topic; Dietary Supplements; Dose-Response Relationship, Drug; Female; Humans; Hypervitaminosis A; Infant, Newborn; Nonprescription Drugs; Perinatal Care; Pregnancy; Pregnancy Complications; United States; United States Food and Drug Administration; Vitamin A; Vitamin A Deficiency; Vitamins

Toxicity has been associated with abuse of vitamin A supplements and with diets extremely high in preformed vitamin A. Consumption of 25,000-50,000 IU/d for periods of several months or more can produce multiple adverse effects. The lowest reported intakes causing toxicity have occurred in persons with liver function compromised by drugs, viral hepatitis, or protein-energy malnutrition. Certain drugs or other chemicals may markedly potentiate vitamin A toxicity in animals. Especially vulnerable groups include children, with adverse effects occurring with intakes as low as 1,500 IU.kg-1.d-1, and pregnant women, with birth defects being associated with maternal intakes as low as approximately 25,000 IU/d. The maternal dose threshold for birth defects cannot be identified from present data. An identifiable fraction of the population surveyed consumes vitamin A supplements at 25,000 IU/d and a few individuals consume much more. beta-Carotene is much less toxic than vitamin A.

Topics: Abnormalities, Drug-Induced; Animals; beta Carotene; Carotenoids; Dose-Response Relationship, Drug; Drug Synergism; Humans; Hypervitaminosis A; Liver Diseases; Vitamin A

A literature review was conducted on adverse effects of carotenoids on human and animal development. The data suggest that beta-carotene administration prevented genetic damage caused by mutagens both in bacterial and cell culture systems, and that large doses of pure beta-carotene do not cause embryotoxicity in rodents. In addition, studies of individuals with congenitally high levels of plasma carotenoids and babies born carotenemic because of their mothers' intake of large amounts of carotenoid-containing foods during pregnancy reveal no abnormalities attributable to the carotenoid molecule.

Topics: Abnormalities, Drug-Induced; Animals; beta Carotene; Carotenoids; Embryo, Mammalian; Female; Humans; Mutagens; Pregnancy

Topics: Abnormalities, Drug-Induced; Antioxidants; beta Carotene; Carotenoids; Female; Humans; Nutritional Requirements; Pregnancy; Publishing; Vitamin A

Topics: Abnormalities, Drug-Induced; beta Carotene; Carotenoids; Female; Humans; Neural Crest; Pregnancy; Vitamin A

Topics: Abnormalities, Drug-Induced; Adult; beta Carotene; Counseling; Female; Humans; Infant, Newborn; Male; Porphyrias; Pregnancy; Pregnancy Outcome; Retinoids; Teratogens; Vitamin A

Topics: Abnormalities, Drug-Induced; Animals; beta Carotene; Carotenoids; Cattle; Diet; Female; Fruit; Humans; Milk; Neoplasms; Pregnancy; Retinoids; Risk; Vegetables; Vitamin A

The safety of beta-carotene, a widely distributed food colorant was assessed in tests with cells and in sub-chronic and chronic experiments with animals. Mutagenicity evaluations which included the standard Ames test and the micro-nucleus test of bone marrow cells from mice showed that beta-carotene exerted no mutagenic properties. Embryotoxicity studies in rats and rabbits showed that there was no evidence of embryotoxicity and a multiple generation study in rats showed that there was no interference with the reproductive function in rats given oral doses of up to 1000 mg/kg/day. Chronic toxicity was studied in a 2-year study with dogs in a toxicity/tumorigenicity study in rats and in a mouse carcinogenicity study. Histological findings in the livers of treated dogs and mice, but not in rats, included vacuolated cells with eccentric nuclei which were distributed in periportal areas and which were frequently associated with minimal lipid deposition. There was no evidence that the vacuolisation was dose-related. It was considered that the vacuolated cells were fat storage cells. There was no effect on the tumor profiles in the rat and the mouse studies.

Topics: Abnormalities, Drug-Induced; Adipose Tissue; Animals; beta Carotene; Blood Coagulation; Body Weight; Carotenoids; Dogs; Female; Liver; Male; Neoplasms, Experimental; Pregnancy; Rabbits; Rats; Rats, Inbred Strains