Aspirin / diphenhydramine Pregnancy and Breastfeeding Warnings

Brand names: Bayer PM

Aspirin / diphenhydramine Pregnancy Warnings

Aspirin has not been formally assigned to pregnancy category by the FDA. However, aspirin is considered to be in pregnancy category D by the FDA if full dose aspirin is taken in the third trimester. Use of nonsteroidal anti-inflammatory drugs during the third trimester of pregnancy should be avoided due to effects on the fetal cardiovascular system (closure of the ductus arteriosus). Aspirin use in pregnancy has been associated with alterations in both maternal and fetal hemostasis. In addition, high doses have been associated with increased perinatal mortality, intrauterine growth retardation, and teratogenic effects. During the first two trimesters of pregnancy, aspirin should only be given during pregnancy when clearly needed and when benefit outweighs risk. In 1990, the FDA issued a warning that it is especially important not to use aspirin during the last trimester of pregnancy unless specifically directed to do so by a physician because it may cause problems in the unborn child or complications during delivery.

Diphenhydramine has been assigned to pregnancy category B by the FDA. Animal studies have failed to reveal teratogenicity. The Collaborative Perinatal Project reported 595 first-trimester exposures and 2,948 exposures anytime during pregnancy. No relationship was found to large categories of malformations. Possible associations with individual malformation were found. One study reported a statistical relationship between diphenhydramine use in the first trimester and cleft palate. One case of withdrawal in an infant whose mother ingested 150 mg per day of diphenhydramine has been reported. This infant developed tremor on the fifth day of life which was treated with phenobarbital. During the first two trimesters of pregnancy, aspirin-diphenhydramine should only be given during pregnancy when clearly needed and when benefit outweighs risk. Aspirin-diphenhydramine should only be given during the last trimester of pregnancy when there are no alternatives and benefit outweighs risk.

Increased maternal bleeding can occur during delivery when aspirin is used 1 week prior to and/or during labor and delivery. Prolonged gestation and labor have been reported due to aspirin's inhibition of prostaglandin.

A study of the use of low-dose aspirin (60 mg per day) to prevent and treat preeclampsia in 9364 pregnant women (the Collaborative Low-dose Aspirin Study in Pregnancy--CLASP) did "not support routine prophylactic or therapeutic administration of antiplatelet therapy in pregnancy to all women at increased risk of preeclampsia or IUGR." In that study, no excess of intraventricular hemorrhage, neonatal bleeds, or mortality attributable to bleeding were observed. The investigators did identify a possible role for low-dose aspirin in the treatment of early-onset preeclampsia severe enough to need very preterm delivery.

Another study of low-dose aspirin (follow-up from the Italian Study of Aspirin in Pregnancy) has suggested that "low dose aspirin in pregnancy is safe with respect to the risks of malformation and of major impairment in development at 18 months of age."

High-dose aspirin (2 g per day) has been associated with stillbirths, cerebral hemorrhage, oculoauriculovertebral dysplasia, neonatal salicylate toxicity, constricted ductus arteriosus, cyclopia, and neonatal acidosis. Some cases of congenital heart defects have been reported. However, a case control study of aspirin use in the first trimester concluded that aspirin "does not increase the risk of congenital heart defects in relation to that of other structural malformations."

A review of prenatal drug use in 3026 women with premature infants demonstrated an increased risk of retrolental fibroplasia with antihistamine use during the last two weeks of pregnancy. The dosage used or the particular antihistamine was not specified. The incidence of retrolental fibroplasia in premature infants exposed in utero to antihistamine during this time was 21% compared to 11% in premature infants not exposed.

Diphenhydramine has been shown to have oxytocic effects in animal and human uteri. One case report of a pregnant woman who ingested a large amount of diphenhydramine in an attempted suicide developed strong, regular uterine contractions that were halted by the administration of intravenous magnesium.

See references

Aspirin / diphenhydramine Breastfeeding Warnings

Aspirin is excreted into human milk in small amounts. Peak milk salicylate levels have been reported at nine hours after maternal dosing (and measured at 1.1 mg/dL). Use of large doses of aspirin can result in rashes, platelet abnormalities, and bleeding in nursing infants. Because of a single case report of metabolic acidosis, the American Academy of Pediatrics characterizes aspirin as a drug that has been "associated with significant effects on some nursing infants and should be given to nursing mothers with caution."

Diphenhydramine is excreted into human milk. Diphenhydramine may also inhibit lactation. The manufacturer recommends that due to the potential for serious adverse reactions in nursing infants, a decision should be made to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.

See references

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer