Tetrax 500

Indications

Tetrax is the preferred treatment for the following infections:

• Rickettsial infections (such as Rocky Mountain spotted fever, endemic and scrub typhus fever, and human ehrlichiosis).
• Mycoplasma pneumoniae infections in adults. These outbreaks of pneumonia, commonly found in barracks and institutions, mostly affect children and young adults. While rare, maculopapular rashes, hemolytic anemia, and meningoencephalitis may occur.
• Chlamydial infections, including Chlamydia psittaci, which causes psittacosis (ornithosis), a systemic illness contracted from infected birds. This infection may lead to extensive pneumonia and severe systemic upset, with headache as a prominent early symptom.
• Non-gonococcal or nonspecific urethritis, referring to inflammation of the urethra not caused by gonococcal, chlamydial, or other specific infectious agents.
• Lyme disease
• Brucellosis
• Miscellaneous infections such as granuloma inguinale, cholera, glanders, relapsing fever, and V. vulnifians.

Other common uses of tetracycline include:

• Urinary tract infections caused by susceptible organisms, including acute urethral syndrome in women.
• Bronchitis in patients with known underlying chronic lung diseases.
• Pelvic inflammatory disease and other sexually transmitted diseases (STDs) regimens.
• Traveler’s diarrhea.
• Acne vulgaris
• Prostatitis.
• As an alternative agent in penicillin-allergic patients with syphilis.
• Anaerobic infections caused by susceptible organisms.

Pharmacology

Tetracycline primarily acts on protein synthesis, with an energy-dependent active transport system facilitating its entry into bacterial cells. Within the cell, it binds specifically to the 30s ribosomes, inhibiting bacterial protein synthesis.

While many Gram-positive aerobic cocci are susceptible, resistance is common among staphylococci, streptococci, and some pneumococci. Tetracycline is not the preferred choice for infections caused by Gram-positive aerobes.

Pseudomonas and many Enterobacteriaceae are resistant to tetracycline. However, it remains effective against some community-acquired E. coli strains, making it suitable for uncomplicated initial UTIs. Tetracycline is also the drug of choice for Brucella species, Calymmatobacterium granulomatis, Vibrio cholerae, and V. vulnificus.

Tetracycline exhibits activity against anaerobic bacteria, and its high concentrations in the gastrointestinal tract can alter the enteric flora.

Dosage & Administration

The typical adult oral dosage of tetracycline is 1-2 g daily, administered in 2-4 divided doses. For children over 8 years old, the recommended dosage is 25-50 mg/kg daily, also given in divided doses.

Tetracycline should preferably be taken one hour before or two hours after meals.

Specific dosing recommendations for various indications include:

• Acne vulgaris: 250 mg four times daily or 500 mg every 12 hours for one week; followed by 125-250 mg daily for several weeks or months, based on individual progress.
• Acute staphylococcal infections: 1-2 g daily in divided doses for 10-14 days.
• Acute streptococcal infections: 1-2 g daily in divided doses for 10 days. Prolonged therapy is necessary to prevent rheumatic fever or glomerulonephritis.
• Amoebiasis: 1 g daily in four divided doses or 500 mg every 12 hours for 7 days, in combination with amoebicidal agents.
• Brucellosis: 500 mg four times daily plus 1 g streptomycin twice daily for one week; followed by 500 mg four times daily (without streptomycin) for another week. Prolonged therapy is required to prevent relapse.