Zuclopenthixol and Breastfeeding

Summary of use during lactation

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.

Drug levels in milk and infant serum

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.

Effects in breastfed infants

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 lactation and breastmilk

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

Alternative drugs to consider

Haloperidol, Olanzapine, Quetiapine, Risperidone

References

1. HasanA FalkaiP WobrockT World Federation of Societies of Biological Psychiatry (WFSBP) Guidelines for Biological Treatment of Schizophrenia. Part 3: Update 2015 management of special circumstances: Depression, suicidality, substance use disorders and pregnancy and lactation. World J Biol Psychiatry 2015 16 142 70 25822804 PubMed
2. UguzF. A new safety scoring system for the use of psychotropic drugs during lactation. Am J Ther 2021 28 e118 e126 30601177 PubMed
3. Aaes-JørgensenT BjørndalF BartelsU Zuclopenthixol levels in serum and breast milk. Psychopharmacology (Berl) 1986 90 417 8 2878463 PubMed
4. MathesonI SkjaeraasenJ Milk concentrations of flupenthixol, nortriptyline and zuclopenthixol and between-breast differences in two patients. Eur J Clin Pharmacol 1988 35 217 20 3191943 PubMed