Doxycycline Vs. Tetracycline: Drug Comparison

Doxycycline is a broad-spectrum antibiotic used to treat a variety of bacterial infections by inhibiting protein synthesis, effectively stopping bacterial growth. Its FDA-approved indications include treatment for respiratory infections, skin infections, sexually transmitted infections, and tick-borne illnesses including Lyme disease and Rocky Mountain spotted fever. Off-label uses may include treating acne as well as certain autoimmune conditions and malaria prevention. Doxycycline is available in oral tablets, capsules, and intravenous forms. Common side effects include nausea, diarrhea, and sun sensitivity. It should not be used during pregnancy or by children under 8 due to risks of tooth discoloration and delayed bone growth.

Tetracycline is a broad-spectrum antibiotic used to treat bacterial infections by inhibiting protein synthesis, which prevents bacteria from growing and reproducing. Some of its FDA-approved indications include the treatment of infections including acne, respiratory tract infections, urinary tract infections, and certain sexually transmitted infections like chlamydia. Off-label uses may include the treatment of rosacea and some tick-borne illnesses, such as Lyme disease. Tetracycline is available in oral capsule form, typically taken two to four times daily. Common side effects include nausea, diarrhea, and sun sensitivity. It should not be used in children under 8 or during pregnancy due to the risk of permanent tooth discoloration and potential effects on bone development.

Tetracycline antibiotic

Tetracycline antibiotic

To reduce the development of drug-resistant bacteria and maintain effectiveness of doxycycline and other antibacterial drugs, doxycycline should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria

To reduce the development of drug-resistant bacteria and maintain the effectiveness of tetracycline and other antibacterial drugs, tetracycline should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria

• Typically taken orally once or twice daily

• Comes in 75 mg and 100 mg capsules

• Typically taken orally twice or four times daily

• Comes in 250 mg and 500 mg capsules

Adverse reactions have been reported in the following systems:

• Gastrointestinal

• Skin

• Renal toxicity

• Hypersensitivity

• Blood

• Other

Adverse reactions have been reported in the following systems:

• Gastrointestinal

• Teeth

• Skin

• Renal toxicity

• Liver

• Hypersensitivity reactions

• Blood

• Hypersensitivity to any of the tetracyclines

• Drug interactions: anticoagulants, penicillin, antacids, bismuth subsalicylate, barbiturates, carbamazepine, phenytoin, methoxyflurane

• Hypersensitivity to any of the tetracyclines

• Drug interactions: penicillin, anticoagulants, methoxyflurane, antacids, oral contraceptives

• The use of drugs of the tetracycline class, including doxycycline, during tooth development (last half of pregnancy, infancy and childhood to the age of 8 years) may cause permanent discoloration of the teeth (yellow-gray-brown)

• Clostridium difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including doxycycline

• Intracranial hypertension (IH, pseudotumor cerebri) has been associated with the use of tetracyclines including doxycycline

• All tetracyclines form a stable calcium complex in any bone-forming tissue

• The antianabolic action of the tetracyclines may cause an increase in BUN

• Photosensitivity manifested by an exaggerated sunburn reaction has been observed in some individuals taking tetracyclines

• Pregnancy: If any tetracycline is used during pregnancy or if the patient becomes pregnant while taking these drugs, the patient should be apprised of the potential hazard to the fetus

• Breastfeeding: Because of the potential for adverse reactions in nursing infants from doxycycline, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother

• Tooth development: The use of drugs of the tetracycline-class during tooth development (last half of pregnancy, infancy and childhood to the age of 8 years) may cause permanent discoloration of the teeth (yellow-gray-brown)

• Clostridium difficile-associated diarrhea

• Sun sensitivity

• Intracranial hypertension

• Skeletal development

• Antianabolic action

• In long-term therapy, perform periodic laboratory evaluation of organ systems, including hematopoietic, renal and hepatic studies

• Pregnancy: Tetracycline drugs should not be used during pregnancy unless absolutely necessary

• Breastfeeding: Because of the potential for serious adverse reaction in nursing infants from tetracyclines, a decision should be made whether to discontinue the drug, taking into account the importance of the drug to the mother

*This information is from the doxycycline label used by Alembic Pharmaceuticals Inc. See the Full Prescribing Information for more complete information. Doxycycline may also be the active ingredient in other medications, and this information may not be accurate for all medications that include the active ingredient doxycycline.

*This information is from the tetracycline hydrochloride label used by Actavis Pharma, Inc. See the Full Prescribing Information for more complete information. Tetracycline may also be the active ingredient in other medications, and this information may not be accurate for all medications that include the active ingredient tetracycline.