Contraindicated last trimester of pregnancy
NSAIDs should be avoided at 20 weeks gestation and later

Risk Summary: Nonsteroidal anti-inflammatory drugs (NSAIDs) use in pregnant women at 30 weeks gestation and later may cause premature closure of the fetal ductus arteriosus; NSAID use at 20 weeks gestation or later may cause fetal renal dysfunction leading to oligohydramnios and, in some cases, neonatal renal impairment.

Comments:
-NSAID use in pregnancy prior to 20 weeks gestation should be based on a benefit-risk assessment; some authorities recommend avoiding NSAIDs throughout pregnancy whenever possible.
-If NSAID use is necessary between 20- and 30-weeks' gestation, limit use to the lowest effective dose for the shortest duration possible; ultrasound monitoring of amniotic fluid should be considered if NSAID use extends beyond 48 hours; if oligohydramnios occurs, discontinue NSAID and treat appropriately.
-NSAID use is not recommended in women attempting to conceive as it may impair female fertility.

Ibuprofen use during the third trimester of pregnancy increases the risk of premature closure of the fetal ductus arteriosus. In animal studies, administration of prostaglandin synthesis inhibitors such as ibuprofen, resulted in increased pre and post-implantation loss. There are no adequate and well-controlled studies of this combination drug in pregnant women.

US FDA Drug Safety Communication (10-2020): The FDA is requiring a new warning be added to NSAID labeling describing the risk of fetal kidney problems that may result in low amniotic fluid. The FDA is recommending pregnant women avoid NSAID use at 20 weeks gestation or later. Through 2017, the FDA has received 35 reports of low amniotic fluid levels or kidney problems in mothers who took NSAIDs while pregnant. Five newborns died; 2 had kidney failure and confirmed low amniotic fluid, 3 had kidney failure without confirmed low amniotic fluid. The low amniotic fluid started as early as 20 weeks of pregnancy. There were 11 reports of low amniotic fluid levels during pregnancy and the fluid volume returned to normal after the NSAID was stopped. The medical literature has reported low amniotic fluid levels with use of NSAIDs for varying amounts of time, ranging from 48 hours to multiple weeks. Complications of prolonged oligohydramnios may include limb contractures and delayed lung maturation. In some postmarketing cases of impaired neonatal renal function, invasive procedures such as exchange transfusion or dialysis were required. In other cases, the condition was reversible within 3 to 6 days of stopping the NSAID and in these cases reappeared when the same NSAID was restarted.

US FDA pregnancy category Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D, and X are being phased out.

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Larger diphenhydramine doses or more prolonged use may cause a decrease in milk supply, especially before lactation is well established. Use at bedtime (after the last feeding of the day) will minimize effects of the drug. For more than occasional use, nonsedating antihistamines are preferred. Ibuprofen is a preferred analgesic/anti-inflammatory agent in nursing mothers because of its low levels in breastmilk, short half-life, and safe use in infants in doses much higher than those excreted in breastmilk.

Caution is recommended

Excreted into human milk: Yes

Comments: Small, occasional doses of diphenhydramine are not expected to cause adverse effects in breastfed infants; ibuprofen is compatible with breastfeeding.

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