Is Zuclopenthixol safe while breastfeeding?

Summary of use during breastfeeding

Zuclopenthixol is not approved for marketing in the United States, by the U.S. Food and Drug Administration, but is available in other countries. Limited information indicates that maternal oral doses of up to 50 mg daily or depot injections of 72 mg every 2 weeks produce low levels in breastmilk and no detectable short-term adverse effects in the breastfed infants. No long-term data are available. One international guideline recommends that women taking zuclopenthixol not breastfeed.[1] However, a safety scoring system finds zuclopenthixol possible to use cautiously during breastfeeding.[2] Until more data are available, zuclopenthixol should be used with careful infant monitoring during breastfeeding.

Effects on the breastfed infant

Six women received zuclopenthixol during nursing. Five of the women were receiving 4 to 50 mg daily by mouth and one was receiving a depot injection of 72 mg every 2 weeks. Their breastfed infants ranged in age from 3 days to 10 months old, 5 of whom were 2 months or under. No immediate adverse effects such infant drowsiness were noted.[3]

Effects on milk supply

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

Levels in milk

Maternal Levels. Six women received zuclopenthixol during nursing. Five of the women were receiving the drug orally and one was receiving a depot injection. Oral dosages ranged from 4 to 50 mg daily of zuclopenthixol and the depot decanoate injection dosage was 72 mg every 2 weeks. Milk samples were obtained in the morning before the first oral dose of the day. Milk zuclopenthixol concentrations for 5 of the patients were between 1 and 2 mcg/L. The patient receiving the high oral dose of 50 mg daily had a breastmilk zuclopenthixol level of about 9 mcg/L.[3]

One woman received zuclopenthixol for depression beginning 2 weeks postpartum. She initially received a dose of 24 mg daily (4 mg in the morning and 20 mg at night), but the dose was reduced to 14 mg daily (4 mg in the morning and 10 mg at night) after 4 days. Seven milk samples in total were obtained on days 2, 3, 6, and 8 of therapy. The average of the milk level with the 24 mg daily dosage was 20 mcg/L and with the 14 mg daily dosage it was 5 mcg/L. The authors estimated that an exclusively breastfed infant would receive 0.8 to 3 mcg/kg daily with the maternal doses given or 0.3 to 0.8% of the maternal weight-adjusted dosage.[4]

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

Alternatives LactMed lists

• Haloperidol
• Olanzapine
• Quetiapine
• Risperidone