Skip to main content

Diltiazem use while Breastfeeding

Medically reviewed by Last updated on Sep 1, 2021.

Drugs containing Diltiazem: Cardizem, Cartia XT, Dilt-XR, Tiadylt ER, Diltiazem Hydrochloride CD, Tiazac, Cardizem CD, Diltiazem Hydrochloride XR, Matzim LA, Cardizem LA, Show all 19 »Diltia XT, Diltiazem Hydrochloride SR, Dilacor XR, Diltiazem Hydrochloride XT, Taztia XT, Cardizem SR, Teczem, Cardizem Monovial, Diltzac

Diltiazem Levels and Effects while Breastfeeding

Summary of Use during Lactation

Based on limited data, amounts of diltiazem ingested by the infant are small and would not be expected to cause any adverse effects in breastfed infants.

Drug Levels

Maternal Levels. In one patient who was 14 days postpartum, peak milk levels of 190 to 230 mcg/L occurred about 2 hours after the dose during an oral regimen of 60 mg four times daily. The levels and time course of the drug in milk closely paralleled serum levels.[1] Using the peak milk level data from this patient, an exclusively breastfed infant would receive an estimated maximum of 0.9% of the maternal weight-adjusted dosage.

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

Nifedipine, Verapamil


Okada M, Inoue H, Nakamura Y et al. Excretion of diltiazem in human milk. N Engl J Med. 1985;312:992-3. [PubMed: 3974691]

Substance Identification

Substance Name


CAS Registry Number


Drug Class

  • Breast Feeding
  • Lactation
  • Antihypertensive Agents
  • Calcium Channel Blockers
  • Antiarrhythmics
  • Vasodilator Agents

Disclaimer: Information presented in this database is not meant as a substitute for professional judgment. You should consult your healthcare provider for breastfeeding advice related to your particular situation. The U.S. government does not warrant or assume any liability or responsibility for the accuracy or completeness of the information on this Site.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.