Pregnancy retinoids

Much recent interest has been aroused by the fact that retinoid compounds, including both retinol and retinoic acid, reduce the incidence of experimentally induced cancer. In addition, 13-czs-retinoic acid taken orally is remarkably effective in treatment of severe cystic acne. s However, both vitamin A and retinoic acid in large doses are teratogenic, i.e., they cause fetal abnormalities. The use of 13-cis-retinoic acid during early phases of pregnancy led to a high incidence of major malformations in infants born.1 11 1... 

Embryotoxicity/teratogenicity is the major drawback in the therapeutic use of retinoids. The exposure of the fetus during the first trimester with oral retinoids is known to produce characteristic malformations.93 There have also been case reports about malformations associated with retinoid embryopathy after the mother had used tretinoin topically during the first trimester of pregnancy 94-96... 

Tretinoin (Retin-A) is applied topically (not in combination with other keratolytics). It may promote UV-induced skin cancer. Tretinoin should be avoided in sunny weather, and in pregnancy. Benefit is seen in about 10 weeks. Adapalene, a synthetic retinoid, may be better tolerated. 

Retinoids are strongly teratogenic (21). Pregnancy should be ruled out and an effective form of contraception must be used for at least 1 month before starting therapy, during therapy, and for at least 1 month (isotretinoin) or 2 years (acitretin) after therapy is stopped. Retinoid-induced teratogenicity has been reviewed (22,23). 

There are few data about the safety of topical retinoids during pregnancy. The risk of teratogenicity of topical tretinoin, if any, appears to be minimal (SEDA-18, 164) (109). However, there is a case report (110). 

Chan A, Hanna M, Abbott M, Keane RJ. Oral retinoids and pregnancy. Med J Aust 1996 165(3) 164-7. 

Isotretinoin is a retinoid, the class of natural and synthetic compounds that exhibit vitamin A activity. It is a naturally occurring metabolite of vitamin A that inhibits sebum production. The US Food and Drug Administration classifies it as Pregnancy Risk Category X. 

AA, azelaic acid blank, N/A PA, physical assessment PT, pregnancy test SA, salicylic acid TR, topical retinoid. 

AA, azelaic acid AN, oral antiandrogen blank, N/A BPO, benzoyl peroxide lab, CBC, chem screen, urinalysis OA, oral antibiotic Ol, oral isotretinoin PA, physical assessment PT, pregnancy test SLA, serum lipid analysis TA, topical antimicrobial TR, topical retinoid. 

Mawson A. Mefloquine use, psychosis, and violence a retinoid toxicity hypothesis. Med Sci Monit Int Med J Exp Chn Res 2013 19 579-83. Nevin RL. Limbic encephalopathy and central vestibulopathy caused by mefloquine a case report. Travel Med Infect Dis 2012 10 144r-51. Nevin RL. Mefloquine gap junction blockade and risk of pregnancy loss. Biol Reprod 2012 87(3) 65,1-9. 

Lucek RW, Colburn WA (1985) Clinical pharmacokinetics of the retinoids. Clin Pharmacokinet 10 38-62 Luecke RH, Wosilait WD, Pearce BA, Young JF (1994) A physiologically based pharmacokinetic computer model for human pregnancy. Teratology 49 90-103... 

In animals, both vitamin A deficiency and an excess of dietary vitamin A or retinoid analogs, at specific critical periods of development, can result in severe developmental defects, and may be lethal to the embryo. The differentiation of cells in the neural crest and the development of the head and sensory organs, nervous system, heart, limbs, and skeleto-muscular system are often affected. Birth defects of a similar nature have occurred in women exposed to excessive dietary vitamin A, or to pharmacologic retinoids for treatment of skin diseases, in early pregnancy. 

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