Summary of Use during Lactation

No information is available on the long-term use of quazepam during breastfeeding. Because the drug and metabolites could accumulate in the breastfed infant, an alternate drug may be preferred, especially while nursing a newborn or preterm infant.

Drug Levels

Quazepam has a half-life of about 41 hours and is extensively metabolized to 2-oxoquazepam, which is in turn metabolized to desalkylflurazepam having a half-life of 47 to 100 hours.

Maternal Levels. Four women received a single dose of quazepam 15 mg orally. Milk was collected at intervals up to 48 hours after the dose. Quazepam reached a maximum milk level averaging 95.8 mcg/L (range 26 to 216 mcg/L) at 3 hours (range 2 to 4 hours) after the dose. The 2-oxoquazepam metabolite reached a maximum milk level averaging 26.1 mcg/L at 3 hours (range 2 to 4 hours) after the dose. Desalkylflurazepam reached a maximum milk level averaging 2 mcg/L at 7 hours (range 4 to 12 hours) after the dose. Over the 48 hours after the dose, about 0.11% of the mother's total dose was excreted into breastmilk. The authors estimated that this amounts to 2.3% of the maternal weight-adjusted dosage. Because of accumulation with repeated administration, an exclusively breastfed infant would receive 0.19% of the mother's absolute dose or about 4% of the maternal weight-adjusted dosage.[1]

Infant Levels. Relevant published information was not found as of the revision date.

Effects in Breastfed Infants

Relevant published information was not found as of the revision date.

Effects on Lactation and Breastmilk

Relevant published information was not found as of the revision date.

Alternate Drugs to Consider

Zaleplon, Zolpidem

References

1.

Hilbert JM, Gural RP, Symchowicz S, Zampaglione N. Excretion of quazepam into human breast milk. J Clin Pharmacol 1984;24:457-62. [PubMed: 6150944]

Substance Name

Quazepam

CAS Registry Number

36735-22-5

Drug Class

Breast Feeding

Lactation

Milk, Human

Hypnotics and Sedatives

Anti-Anxiety Agents

Benzodiazepines