U.S. flag

An official website of the United States government

NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.

Drugs and Lactation Database (LactMed®) [Internet]. Bethesda (MD): National Institute of Child Health and Human Development; 2006-.

Cover of Drugs and Lactation Database (LactMed®)

Drugs and Lactation Database (LactMed®) [Internet].

Show details


Last Revision: January 18, 2021.

Estimated reading time: 1 minute

CASRN: 127-33-3

image 134974056 in the ncbi pubchem database

Drug Levels and Effects

Summary of Use during Lactation

A number of reviews have stated that tetracyclines are contraindicated during breastfeeding because of possible staining of infants' dental enamel or bone deposition. However, a close examination of available literature indicates that there is not likely to be harm in short-term use of demeclocycline during lactation because milk levels are low and absorption by the infant is inhibited by the calcium in breastmilk. Short-term use of demeclocycline is acceptable in nursing mothers. As a theoretical precaution, avoid prolonged or repeat courses during nursing. Monitor the infant for rash and for possible effects on the gastrointestinal flora, such as diarrhea or candidiasis (thrush, diaper rash).

Drug Levels

Maternal Levels. In 9 women, colostrum levels of demeclocycline ranged from 50 mcg/L to 1 mg/L during a dosage regimen of oral demeclocycline 600 mg daily for 1 to 5 days. Low levels of the drug were detectable in milk for up to 6 days after discontinuation of the drug.[1]

Thirty-six women were studied after receiving oral demeclocycline 300 mg daily for 1 to 9 days after delivery. Demeclocycline was undetectable in milk after a single dose of 300 mg. After repeated doses, milk levels ranged from undetectable to 1.4 mg/L at various times after the dose.[1]

Using the data above, it is estimated that a breastfed infant would receive a maximum of 200 to 300 mcg daily.[1,2]

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

Doxycycline, Tetracycline


von Kobyletzki D, Strauch D. Z Geburtshilfe Gynakol. 1962;159:246–51. [Demethylchloreteracycline in the umbilical vein blood and the amniotic fluid] [PubMed: 14042216]
von Kobyletzki D. Med Welt. 1968;38:2010–9. [Personal studies on pharmacokinetics during the peripartal and nursing period] [PubMed: 5712895]

Substance Identification

Substance Name


CAS Registry Number


Drug Class

Breast Feeding


Anti-Infective Agents

Antibacterial 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.

Copyright Notice

Attribution Statement: LactMed is a registered trademark of the U.S. Department of Health and Human Services.

Bookshelf ID: NBK501715PMID: 30000775


Related information

Similar articles in PubMed

  • Review Tetracycline.[Drugs and Lactation Database (...]
    Review Tetracycline.
    . Drugs and Lactation Database (LactMed®). 2006
  • Review Minocycline.[Drugs and Lactation Database (...]
    Review Minocycline.
    . Drugs and Lactation Database (LactMed®). 2006
  • Review Doxycycline.[Drugs and Lactation Database (...]
    Review Doxycycline.
    . Drugs and Lactation Database (LactMed®). 2006
  • Review Oxytetracycline.[Drugs and Lactation Database (...]
    Review Oxytetracycline.
    . Drugs and Lactation Database (LactMed®). 2006
  • Review Tigecycline.[Drugs and Lactation Database (...]
    Review Tigecycline.
    . Drugs and Lactation Database (LactMed®). 2006
See reviews...See all...

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...