What is tetracycline, and how does it work (mechanism of action)?
Tetracycline is a broad spectrum antibiotic, that is, it is active against many different types of bacteria. It is effective against Hemophilus influenzae, Streptococcus pneumoniae, Mycoplasma pneumoniae, Chlamydia psittaci, Chlamydia trachomatis, Neisseria gonorrhoeae, and many others. Tetracycline prevents growth of bacteria by preventing the bacteria from manufacturing proteins that they need to survive. The first drug of the tetracycline family, chlortetracycline, was introduced in 1948.
Is tetracycline available as a generic drug?
Yes
Do I need a prescription for tetracycline?
Yes
What are the side effects of tetracycline?
Tetracycline is generally well-tolerated. The most common side effects are:
- diarrhea or loose stools,
- nausea,
- abdominal pain,
- rash,
- vomiting.
- headache and
- dizziness
Tetracycline may cause discoloration of teeth if used in patients below 8 years of age. Exaggerated sunburn can occur with tetracycline (photosensitivity). Therefore, sunlight or sunlamp exposure should be minimized during treatment.

QUESTION
What is pneumonia? See AnswerWhat is the dosage for tetracycline?
Food or dairy products reduce the absorption of tetracycline. Therefore, tetracycline should be taken at least two hours before or after meals. For most infections, tetracycline is taken two to four times daily for 7 to 14 days. The usual adult dose is 1-2 g/day in 2 or 4 divided doses.
Is tetracycline safe to take if I'm pregnant or breastfeeding?
Tetracycline is secreted into breast milk. Since tetracycline can impair the development of bone in infants, nursing mothers should not use tetracycline.
What else should I know about tetracycline?
What preparations of tetracycline are available?
Capsules: 250 and 500 mg; Oral Suspension: 125 mg/5 ml (teaspoon).
How should I keep tetracycline stored?
Tetracycline should be stored below 30 C (86 F).
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Summary
Tetracycline (Sumycin, discontinued) is a medication that is used for treating several types of infections. Examples of infections include infections of the respiratory tract, urinary tract, and skin; urethritis, typhus, Rocky Mountain spotted fever, certain sexually transmitted diseases (STDs), acne, anthrax, cholera, and H. pylori. Side effects and drug interactions should be reviewed prior to taking tetracycline (Achromycin, Sumycin).
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Pseudotumor Cerebri (Idiopathic Intracranial Hypertension)
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