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Brian J. Werth

, PharmD, University of Washington School of Pharmacy

Last full review/revision Jul 2020| Content last modified Jul 2020

Tetracyclines are a group of antibiotics used to treat many different bacterial infections.

Tetracyclines include the following:

  • Doxycycline
  • Eravacycline
  • Minocycline
  • Omadacycline
  • Tetracycline

Tetracyclines are usually taken by mouth and work by preventing bacteria from producing proteins they need to grow and multiply.

Tetracyclines should not be taken with products that contain aluminum, calcium, magnesium, or iron. Such products include some antacids and many vitamin and mineral supplements.

Tetracycline and omadacycline should be taken with plenty of water when the stomach is empty because food, especially dairy products such as milk, yogurt, cheese, and ice cream, reduces its absorption (the movement of a drug into the bloodstream after it is given by mouth).

Minocycline and doxycycline can be taken with or without food because food does not reduce their absorption.

Doxycycline, minocycline, and tetracycline can be given by injection as well as by mouth. Eravacycline can be given only by injection in a vein.



Common Uses

Some Side Effects







Chlamydial infections

Lyme disease

Mycoplasmal infections

Rickettsial infections

Skin infections caused by susceptible bacteria that are resistant to other antibiotics, including methicillin-resistant Staphylococcus aureus (MRSA)

Gastrointestinal upset

Sensitivity to sunlight

Staining of teeth in the fetus if used late in pregnancy or if taken by children under 8 years of age

(See also Overview of Antibiotics.)

Use of Tetracyclines During Pregnancy and Breastfeeding

Pregnant women should not take tetracyclines. These drugs can affect tooth and bone development in the fetus and, if taken late in pregnancy, can cause permanent staining of the fetus's teeth. (See also Drug Use During Pregnancy.)

Use of tetracyclines during breastfeeding is usually discouraged. (See also Drug Use During Breastfeeding.)

Drugs Mentioned In This Article

Generic Name Select Brand Names
Tetracycline ACHROMYCIN V
Eravacycline Eravacycline
Minocycline MINOCIN

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