Drug nameFDA pregnancy risk classification by trimester (1st/2nd/3rd)Drug classCrosses placenta?Use in pregnancy
Kaolin and pectin (Kaopectate)B/B/BAntidiarrhealNoAntidiarrheal of choice (not absorbed)
Bismuth subsalicylate (Pepto Bismol)C/C/DAntidiarrhealYesNot recommended (salicylate absorption)
Loperamide (Imodium)B/B/BAntidiarrhealNot knownProbably safe*
Atropine/diphenoxylate (Lomotil)C/C/CAntidiarrhealNot knownNot recommended (adverse animal studies)