Is Tinidazole 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 Tinidazole. The text below is quoted from that source — it is not our own verdict.
Summary of use during breastfeeding
Amounts of tinidazole in milk are less than doses given to infants. Measurements of infant plasma levels during breastfeeding have not been reported. No studies have evaluated adverse effects of tinidazole on the infant during breastfeeding, but presumably they are similar to those of the closely related drug, metronidazole, such as increased risk of oral and rectal Candida infections.
As with metronidazole, concern has been raised about exposure of healthy infants to tinidazole via breastmilk,[1] because of possible mutagenicity and carcinogenicity. Opinions vary among experts on the advisability of using tinidazole during longer-term therapy while breastfeeding, but avoidance of breastfeeding for 3 days after a single dose should allow milk levels to drop to negligible values.[2] Other drugs are available for bacterial vaginosis, and can be given vaginally, which should result in lower amounts in breastmilk.
Effects on the breastfed infant
Relevant published information was not found as of the revision date.
Effects on milk supply
Relevant published information was not found as of the revision date.
Levels in milk
Maternal Levels. Three women were given tinidazole 150 orally twice daily starting on day 4 postpartum. On day 7, milk samples were collected at 2, 5 and 9 hours after a dose. Breastmilk concentrations ranged between 5.8 and 12.7 mg/L.[3]
Twenty-four women who delivered by cesarean section were given a single intravenous dose of tinidazole 500 mg after cord clamping. Colostrum levels of tinidazole averaged 5.8 mg/L at 12 hours after the dose, 3.5 mg/L at 24 hours, 1.2 mg/L at 48 hours and 0.3 mg/L at 72 hours after the dose. The drug was barely detectable 96 hours after the dose. Only slight differences existed between concentrations in fore- and hindmilk.[4]
Five women who delivered by cesarean section were given a single intravenous dose of tinidazole 1600 mg after cord clamping. Milk concentrations and volumes were measured for 96 hours after the dose. The authors concluded that milk concentrations would be sufficiently low to commence breastfeeding 72 hours after the dose.[2]
Infant Levels. Relevant published information was not found as of the revision date.
Alternatives LactMed lists
“No published information” means the studies do not exist yet — not that Tinidazole is known to be harmful, and not that it is known to be safe. Your prescriber or pharmacist can weigh your baby's age and whether a better-studied alternative would do the same job. Worth asking before stopping a medicine you need.
Source: Drugs and Lactation Database (LactMed), National Institute of Child Health and Human Development (NICHD), via NCBI Bookshelf, record “Tinidazole” (LM441). 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.