tetracycline, Sumycin (Discontinued) (cont.)

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Medical and Pharmacy Editor:

DOSING: 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.

DRUG INTERACTIONS: Tetracycline should not be taken at the same time as aluminum, magnesium, or calcium-based antacids (for example, aluminum with magnesium hydroxide-oral [Mylanta, Maalox], calcium carbonate [Tums, Rolaids]); iron supplements; bismuth subsalicylate (Pepto-Bismol), and dairy products. These agents bind tetracycline in the intestine and reduce its absorption into the body.

Tetracycline may enhance the activity of the blood thinner, warfarin (Coumadin), and result in excessive "thinning" of the blood, necessitating a reduction in the dose of warfarin. Phenytoin (Dilantin), carbamazepine (Tegretol), and barbiturates (such as phenobarbital) may enhance the elimination of tetracycline and reduce the effectiveness of tetracycline. Tetracycline may reduce the effectiveness of oral contraceptives.

PREGNANCY: Tetracycline antibiotics can impair development of bone in the fetus. Therefore, tetracycline is not recommended during pregnancy unless there is no other appropriate antibiotic.

NURSING MOTHERS: Tetracycline is secreted into breast milk. Since tetracycline can impair the development of bone in infants, nursing mothers should not use tetracycline.

SIDE EFFECTS: Tetracycline is generally well-tolerated. The most common side effects are diarrhea or loose stools, nausea, abdominal pain, rash, and vomiting. Headache and dizziness may also occur. 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.

Reference: FDA Prescribing Information


Medically Reviewed by a Doctor on 4/4/2013


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