Is Lorazepam safe while breastfeeding?
Here is what LactMed, the Drugs and Lactation Database published by the U.S. National Institute of Child Health and Human Development (NICHD), reports about Lorazepam. The text below is quoted from that source — it is not our own verdict.
Summary of use during breastfeeding
Lorazepam has low levels in breastmilk, a short half-life relative to many other benzodiazepines, and is safely administered directly to infants. Evidence from nursing mothers indicates that lorazepam does not cause any adverse effects in breastfed infants with usual maternal dosages. Monitor the infant for sedation, poor feeding and poor weight gain.
Effects on the breastfed infant
The newborn infant of a mother taking 2.5 mg of lorazepam orally twice daily for 5 days after delivery showed no signs of sedation.[2]
In a telephone follow-up study, 124 mothers who took a benzodiazepine while nursing reported whether their infants had any signs of sedation. Sixty-four mothers took lorazepam while breastfeeding and none reported sedation in her infant.[6]
A prospective cohort study of infants breastfed by mothers in an inpatient mother-baby psychiatric unit in India followed 7 infants who were exposed to risperidone in breastmilk; most received partial supplementation. One infant whose mother was taking risperidone 4 mg and lorazepam 2 mg developed sedation that resolved when lorazepam was discontinued.[7]
A mother took 1 mg of lorazepam as needed. No adverse effects occurred in her 6.5-month-old breastfed infant over the next 24 hours.[5]
Effects on milk supply
A study retrieved pharmacovigilance data on lorazepam from the FDA’s FAERS database and the EU’s Eudravigilance database. FAERS identified 25 reports of lorazepam exposure via human milk and Eudravigilance just one. Central nervous system (CNS) related symptoms were reported, but in all these cases, lorazepam was part of CNS polypharmacy. No lorazepam monotherapy related events were found.[5]
Levels in milk
Maternal Levels. Four women were given 3.5 mg of lorazepam orally 2 hours before undergoing cesarean section. Colostrum levels of lorazepam averaged 8.5 mcg/L at 4 hours after the dose; conjugated lorazepam metabolites were not measured.[1]
Another woman taking lorazepam 2.5 mg orally twice a day for the first 5 days postpartum had milk levels of free and conjugated lorazepam of 12 and 35 mcg/L, respectively, at an unspecified time on day 5.[2] Since infants can deconjugate and absorb glucuronides, the total drug level is probably more important than the free drug alone. Using the total amount excreted, an exclusively breastfed infant would receive about 7 mcg/kg daily with this maternal dosage or about 8.5% of the maternal weight-adjusted dosage.
A woman who was 4 weeks postpartum was taking lorazepam 2.5 mg 1 to 3 times daily and lormetazepam, which is partially metabolized to lorazepam, 2 mg once daily. On day 5 of therapy after taking 2 doses of lorazepam in the previous 8 hours, her lorazepam milk level was 123 mcg/L. On day 6 after having taken 3 doses in the previous 24 hours, her milk lorazepam level was 89 mcg/L. On day 7, milk levels were 55 and 40 mcg/L at 14 and 18.5 hours after her last dose, respectively.[3]
Three women who were taking oral lorazepam 0.5 mg daily donated milk samples between 3 and 6 days postpartum at 2 hours after a dose at the estimated peak serum concentration and just before a dose. One woman who was taking a dose of 1 mg daily had a 2-hour milk level of 1.64 mcg/L and a trough milk level of 0.826 mcg/L. The other 2 women 2-hour milk levels of 1.72 and 1.98 mcg/L. Both had trough milk levels less than the lower limit of quantification of 0.5 mcg/L.[4]
A woman who was nursing her 6.5-month-old infant took a single dose of 1 mg of lorazepam. Six milk samples were taken between 1.5 and 23.1 hours after the dose. All were below the lower limit of quantification of 5 mcg/L. Semi-quantitative levels indicated that the highest milk value of 2.1 mcg/L occurred at 1.5 hours after the dose and decreased to 0.65 mcg/L at 23.1 hours. The authors estimated an RID ranging from 1.35% to 1.80% using standard milk intake values.[5]
Infant Levels. Relevant published information was not found as of the revision date.
Alternatives LactMed lists
Lorazepam in pregnancy
LactMed covers breastfeeding only. For what the NHS and the US prescribing label say about pregnancy, see:
Source: Drugs and Lactation Database (LactMed), National Institute of Child Health and Human Development (NICHD), via NCBI Bookshelf, record “Lorazepam” (LM364). LactMed on NCBI Bookshelf. LactMed is a registered trademark of the U.S. Department of Health and Human Services.
Educational summary of an authoritative source — not medical advice. Never start, stop, or change a medicine while breastfeeding without confirming with your doctor.