Minocycline

Pregnancy

Minocycline crosses the placenta so when taken during pregnancy it is transferred to the fetus and can cause harm to the fetus. There have been reports of birth defects, including limb reduction, and spontaneous abortion, but a causal association cannot be established because of little available data. Repeated or long-term use of minocycline during pregnancy may also lead to a permanent discoloration of teeth because minocycline accumulates in teeth and bones. 

Minocycline can cause birth defects in the baby even if the father of the child is the one using minocycline. Both males and females should inform their doctor of any medications they are on when planning a pregnancy.

Category: D 

Category A

Adequate and well-controlled studies have failed to demonstrate a risk to the fetus in the first trimester of pregnancy (and there is no evidence of risk in later trimesters).

Category B

Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women.

Category C

Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

Category D

There is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience or studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

Category X

Studies in animals or humans have demonstrated fetal abnormalities and/or there is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience, and the risks involved in use of the drug in pregnant women clearly outweigh potential benefits.

Breastfeeding

Excretion into human milk: Yes

Prolonged or repeated use of minocycline should be avoided during breastfeeding. Minocycline is excreted into breast milk possibly causing discoloration of teeth and slowing down the growth of bones. Minocycline may also disturb the normal gut bacteria causing diarrhea or a fungal infection (thrush, diaper rash). 

Studies suggest that minocycline may alter breast milk production and/or composition.

Black discoloration of breast milk has been reported when using minocycline.