Megadox 100

Indications

Megadox treats various infections caused by susceptible microorganisms:

• Respiratory tract infections: Pneumonia, influenza, sinusitis, bronchitis, tonsillitis, tracheitis.
• Gastrointestinal tract infections: Cholera, traveler’s diarrhea, shigella dysentery, acute intestinal amebiasis.
• Chlamydial infections: Lympho-granuloma venereum, psittacosis, trachoma.
• Sexually transmitted diseases: Non-gonococcal urethritis, acute pelvic inflammatory disease, urethral and endocervical or rectal infections, gonorrhea, syphilis, pyelonephritis, cystitis.
• Other infections: Impetigo, furunculosis, inclusion conjunctivitis, brucellosis, tularemia, cellulitis, acne, Q-fever.

Description

Megadox is a potent broad-spectrum antibiotic from the tetracycline group, effective against a wide range of bacteria including Gram-positive and Gram-negative types, spirochetes, mycoplasma, rickettsia, and mycobacteria. It is an alternative to penicillin for treating gonorrhea and syphilis, primarily inhibiting bacterial protein synthesis.

Pharmacology

Doxycycline Hydrochloride, a semisynthetic tetracycline, exhibits broad-spectrum bacteriostatic activity. It is particularly active against Staphylococcus aureus and Nocardia, including penicillin-resistant strains. Doxycycline also shows efficacy against certain Gram-negative bacteria and anaerobes, making it useful in treating infections such as Haemophilus influenzae, H. ducreyi, Actinomyces, Brucella, and Vibrio cholerae, as well as Chlamydia, Mycoplasma, and various Rickettsiae.

Dosage

Standard dose: 200 mg on the first day, followed by 100 mg daily for 7-10 days. Severe infections: 200 mg daily for 10 days. Acne: 100 mg daily. Genital chlamydia, non-gonococcal urethritis: 100 mg twice daily for 7-21 days (14-21 days for pelvic inflammatory disease).

Administration

Capsules should be swallowed whole with plenty of fluids during meals while sitting or standing.

Interaction

Tetracycline absorption is hindered by antacids containing aluminum, calcium, or magnesium, as well as iron preparations and bismuth salicylate. Barbiturates, carbamazepine, and phenytoin decrease doxycycline’s half-life. Concurrent use with tetracyclines may reduce oral contraceptive effectiveness. Adjust anticoagulant dosages accordingly and avoid combining with penicillin.

Contraindications

Doxycycline is contraindicated in patients hypersensitive to tetracyclines, children under 8 years old, pregnant women, and lactating mothers.

Side Effects

Possible side effects include nausea, vomiting, diarrhea, skin rashes, hemolytic anemia, and eosinophilia.

Pregnancy & Lactation

Avoid doxycycline during pregnancy due to potential effects on fetal bone growth and tooth discoloration. It passes into breast milk, so nursing mothers should not use it.

Precautions & Warnings

Avoid using tetracyclines during tooth development stages (last half of pregnancy, infancy, and childhood up to 8 years) to prevent permanent tooth discoloration.

Therapeutic Class

Tetracycline antibiotic.

Storage Conditions

Store in a cool, dry place away from light. Keep out of reach of children.