GENERIC NAME: tetracycline

BRAND NAME: Achromycin; Sumycin

DRUG CLASS AND MECHANISM: Tetracycline is a broad-spectrum antibiotic. It is effective against a wide variety of bacteria including Hemophilus influenzae, Streptococcus pneumoniae, Mycoplasma pneumoniae, Chlamydia psittaci, Chlamydia trachomatis, Neisseria gonorrhoeae, and many others. The first drug of the tetracycline family, chlortetracycline, was introduced in 1948.

PRESCRIPTION: yes

GENERIC AVAILABLE: yes

PREPARATIONS: Capsules: 250mg, 500mg; Tablets: 250mg, 500mg; Syrup: 125 mg/teaspoon.

STORAGE: Capsules should be kept below 30°C (86°F).

PRESCRIBED FOR: Tetracycline is used for many different infections including respiratory tract infections due to Hemophilus influenzae, Streptococcus pneumoniae, or Mycoplasma pneumoniae. It also is used for nongonococcal urethritis (due to Ureaplasma), Rocky mountain spotted fever, typhus, chancroid, cholera, brucellosis, anthrax, syphilis and acne. It is used in combination with other medications to treat Helicobacter pylori, the bacteria associated with ulcers of the stomach and duodenum.

DOSING: Tetracycline should be taken at least one hour before or two hours after meals to prevent binding to food and the resulting reduced absorption of the tetracycline. For most infections, tetracycline is taken two to four times daily for 7 to 14 days.

DRUG INTERACTIONS: It is recommended that tetracycline not be taken at the same time as aluminum-, magnesium-, or calcium- based antacids, such as Mylanta, Maalox, Tums, or Rolaids since, like food, these compounds bind tetracycline in the intestine. Similarly, tetracycline should not be taken with minerals (such as calcium or iron), with bismuth subsalicylate (Pepto-Bismol) or with dairy products.

Tetracycline may enhance the activity of 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) can enhance the metabolism of tetracycline.

PREGNANCY: Tetracycline antibiotics can have toxic effects on development of bone in the fetus. Therefore, tetracyclines are not recommended during pregnancy unless there is no other appropriate antibiotic.

NURSING MOTHERS: Tetracycline is secreted into breast milk. Since tetracyclines can cause decreased development of bone, the use of tetracycline in nursing mothers is of concern. The physician must decide whether to avoid nursing during treatment or to use a different antibiotic.

SIDE EFFECTS: Tetracycline is generally well-tolerated. The most common side effects are diarrhea or loose stools, nausea, abdominal pain, and vomiting. Tetracyclines may cause discoloration of teeth if used in patients below 8 years of age. Exaggerated sunburn can occur with tetracyclines; therefore, sunlight should be minimized during treatment.