CATEGORIES OF DRUGS IN RELATION TO PREGNANCY

 

INTRODUCTION:  Drug use during pregnancy is one of the most important threats to worry about in order to ensure the safety of the mother and the baby.  In the first place although the mother may have less or no effect, our fear rotates around the growing fetus that may take in the drug via the placenta and develop fetal malformations.

1.  RISK CATEGORY A

INTERPRETATION: Adequate, well-controlled studies in pregnant women have not shown an increased risk of fetal abnormalities to the fetus in any trimester of pregnancy.

EXAMPLE OF DRUGS: Prenatal multivitamins, insulin, thyroxine, folic acid.

2.  RISK CATEGORY B

INTERPRETATION: Animal studies have revealed no evidence of harm to the fetus; however, there are no adequate and well-controlled studies in pregnant women.

OR

Animal studies have shown an adverse effect, but adequate and well-controlled studies in pregnant women have failed to demonstrate risk to the fetus in any trimester.

EXAMPLE OF DRUGS: Penicillins, cephalosporins, azithromycin, acetaminophen, ibuprofen in the first and second trimesters.

3.  RISK CATEGORY C

INTERPRETATION: Animal studies have shown an adverse effect and there are no adequate and well controlled studies in pregnant women.

OR

No animal studies have been conducted and there are no adequate and well controlled studies in pregnant women.

EXAMPLE OF DRUGS: Most prescription medicines; antimicrobials such as clarithromycin, fluoroquinolones, and Bactrim; selective serotonin reuptake inhibitors (SSRIs); corticosteroids; and most antihypertensives.

4.  RISK CATEGORY D

INTERPRETATION: Adequate well-controlled or observational studies in pregnant women have demonstrated a risk to the fetus. However, the benefits of therapy may outweigh the potential risk. For example, the drug may be acceptable if needed in a life-threatening situation or serious disease for which safer drugs cannot be used or are ineffective.

EXAMPLE OF DRUGS: Alcohol, ACE inhibitors, angiotensin receptor blockers (ARBs) in the second and third trimesters, gentamicin, carbamazepine, cyclophosphamide, lithium carbonate, methimazole, mitomycin, nicotine, nonsteroidal antiinflammatory drugs (NSAIDs) in the third trimester, phenytoin, propylthiouracil, streptomycin, tetracyclines, valproic acid.

5.  RISK CATEGORY X

INTERPRETATION: Adequate well-controlled or observational studies in animals or pregnant women have demonstrated positive evidence of fetal abnormalities or risks. The use of the product is contraindicated in women who are or may become pregnant. There is no indication for use in pregnancy.

EXAMPLE OF DRUGS: Clomiphene, fluorouracil, isotretinoin, leuprolide, menotropins, methotrexate, misoprostol, nafarelin, oral contraceptives, raloxifene, ribavirin, statins, temazepam, testosterone and thalidomide, and warfarin.

RELATED;

1.  HEMORRHAGIC DISEASE OF THE NEW BORN  

2.  ENDOMETRIOSIS

3.  OBSTETRICS AND GYNECOLOGY

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