ABC

D

X

PregnancyPregnancyRiskRiskCategoriesCategories(PRC) – FDA(PRC) – FDA

The FDA (USA) has established 5 categoriesto indicate the potential of systematically absorbed drug for causing birth defects. Thekey differentiation among the categoriesrests upon the reliability of documentationand the risk:benefit ratio (Lacy et al., 1998).

Thalidomide (1957 – 1961)

PRC A: Controlled studies in pregnant women fail todemonstrate a risk to the fetus in the first trimester withno evidence of risk in later trimesters. The possibility offetal harm appears remote. Examples: Folic acid, T4, Magnesium sulfate (inj.!)PRC B: The animal-reproduction studies have not demonstrated a fetal risk but there are no controlled studies in pregnant women, or animal-reproductionstudies have shown an ARs (other than a decrease infertility) that was not confirmed in controlled studies inwomen in the first trimester and there is no evidence of later trimesters. Examples: penicillins, erythromycin,paracetamol, lidocaine.

PRC C: The studies in animals have revealed ARs on the fetus (teratogenic, embryocidal or other effects)and there are no controlled studies in women, or studiesin women are not available. Drug should be given onlyif the potential benefits justify the potential risk to the fetus.Examples: atropine, adrenaline, thiopental, bisoprolol.PRC D: There is positive evidence of human fetal risk,but the benefits from use in pregnant women may beacceptable despite the risk (e.g. if the drug is needed ina life-threatening situation or for a serious disease forwhich safer drugs cannot be used are ineffective.).Examples: phenytoin, valproate, diazepam, cyclophosphamide.

PRC X: Studies in animals or human beings have demonstrated fetal abnormalities or there is evidenceof fetal risk based on human experience, or both, andthe risk of the use of the drug in pregnant women clearlyoutweighs any possible benefit. The drug is contraindi-cated in women who are or may become pregnant.Examples: thalidomide, estrogens,isotretionoin, ergometrine.

Lactation Risk Categories – LRC)Lactation Risk Categories – LRC)

L1 – safest: Paracetamol, Ibuprofen, Epinephrine.

LACTATION RISK CATEGORIES (LRC) (Hale, 2004; 2008):

L2 – safer: Diclofenac, Fentanyl, Cetirizine, Omeprazole, cephalosporins.

L3 – moderately safe: Acarbose, Acetylsalicylic acid, Indometacin, Codeine, Morphine, Midazolam, Triazolam, Acebutоlol, Dimetinden. L4 – hazardous: Colchicine, Lithium, Ergobrevine, Ergotamine.

L5 – contraindicated: ACE inhibitors (enalapril etc.)

Goodman & Gilman's The PharmacologicBasis of Therapeutics - 11th Ed. (2006)

Goodman & Gilman's The PharmacologicBasis of Therapeutics - 11th Ed. (2006)

PRCsPRCs LRCsLRCs AA:: controlled studies controlled studies

show no riskshow no risk

BB:: no evidence of risk in no evidence of risk in

humanshumans

CC:: risk cannot be ruled risk cannot be ruled

outout

DD:: positive evidence of positive evidence of

riskrisk

XX:: contraindicated in contraindicated in

pregnancypregnancy

L1L1:: safest safest

L2L2:: safer safer

L3L3:: moderately safe moderately safe

L4L4:: possibly hazardous possibly hazardous

L5L5:: contraindicated contraindicated