Mode of Action of Tetracycline
Tetracyclines are primarily bacteriostatic and exert their antimicrobial effect by the inhibition of protein synthesis by binding to the 30S ribosomal subunit. Tetracycline is active against a broad range of gram-negative and gram-positive organisms.
Drug Label Information | Brands:
Brands of Tetracycline in Kenya
Fidemycin®, Dawa Limited
Racycline®, Lab and Allied
Tetrazen 250®,Zenufa Laboratories
Unitet®, Universal Corporation Ltd (UCL)
Tetracycline is indicated in the treatment of infections caused by susceptible strains of the designated organisms in the conditions listed below:
- Upper respiratory tract infections caused by Streptococcus pyogenes, Streptococcus pneumoniae and Haemophilus influenzae. Note: Tetracycline should not be used for streptococcal disease unless the organism has been demonstrated to be susceptible.
- Lower respiratory tract infections caused by Streptococcus pyogenes, Streptococcus pneumoniae, Mycoplasma pneumoniae (Eaton agent, and Klebsiella sp.)
- Skin and soft tissue infections caused by Streptococcus pyogenes, Staphylococcus aureus.
(Tetracyclines are not the drugs of choice in the treatment of any type of staphylococcal infections.)
- Infections caused by rickettsia including Rocky Mountain spotted fever, typhus group infections, Q fever, rickettsialpox.
- Psittacosis caused by Chlamydophila psittaci.
- Infections caused by Chlamydia trachomatis such as uncomplicated urethral, endocervical or rectal infections, inclusion conjunctivitis, trachoma, and lymphogranuloma venereum.
- Granuloma inquinale caused by Klebsiella granulomatis.
- Relapsing fever caused by Borrelia sp.
- Bartonellosis caused by Bartonella bacill iformis.
- Chancroid caused by Haemophilus ducreyi.
- Tularemia caused by Francisella tularensis.
- Plaque caused by Yersinia pestis.
- Cholera caused by Vibrio cholerae.
- Brucellosis caused by Brucella species (tetracycline may be used in conjunction with an aminoglycoside).
- Infections due to Campylobacter fetus.
- As adjunctive therapy in intestinal amebiasis caused by Entamoeba histolytica.
- Urinary tract infections caused by susceptible strains of Escherichia coli, Klebsiella, etc.
- Other infections caused by susceptible gram-negative organisms such as E. coli, Enterobacter aerogenes, Shigella sp., Acinetobacter sp., Klebsiella sp., and Bacteroides sp.
- In severe acne, adjunctive therapy with tetracycline may be useful.
- When penicillin is contraindicated, tetracyclines are alternative drugs in the treatment of the following infections:
- Syphilis and yaws caused by Treponema pallidum and pertenue, respectively,
- Vincent’s infection caused by Fusobacterium fusiforme,
- Infections caused by Neisseria gonorrhoeae,
- Anthrax caused by Bacillus anthracis,
- Infections due to Listeria monocytogenes,
- Actinomycosis caused by Actinomyces species,
- Infections due to Clostridium species.
This drug is contraindicated in persons who have shown hypersensitivity to any of the tetracyclines.
ADVERSE DRUG REACTIONS
anorexia, nausea, epigastric distress, vomiting, diarrhea, glossitis, black hairy tongue, dysphagia, enterocolitis, and inflammatory lesions (with Candida overgrowth) in the anogenital region.
Esophagitis and esophageal ulceration have been reported in patients receiving particularly the capsule and also the tablet forms of tetracyclines. Most of the patients were reported to have taken medication immediately before going to bed
permanent discoloration of teeth may be caused during tooth development. Enamel hypoplasia has been reported
maculopapular and erythematous rashes. Exfoliative dermatitis has been reported. Onycholysis and discoloration of the nails have been reported. Photosensitivity has been reported
an increase in BUN has been reported and is dose related.
hepatotoxicity and liver failure have been observed in patients receiving tetracycline and in tetracycline-treated patients with renal impairment.
urticaria, angioneurotic edema, anaphylaxis, anaphylactoid purpura, pericarditis, exacerbation of systemic lupus erythematosus, and serum sickness-like reactions, as fever, rash, and arthralgia.
hemolytic anemia, thrombocytopenia, thrombocytopenic purpura, neutropenia and eosinophilia have been reported.
When given over prolonged periods, tetracyclines have been reported to produce brown-black microscopic discoloration of thyroid glands. No abnormalities of thyroid function studies are known to occur.
- Since bacteriostatic drugs may interfere with the bactericidal action of penicillin, it is advisable to avoid giving tetracycline in conjunction with penicillin or other bactericidal antibacterials.
- Because the tetracyclines have been shown to depress plasma prothrombin activity, patients who are on anticoagulant therapy may require downward adjustment of their anticoagulant dosage.
- The concurrent use of tetracycline and methoxyflurane has been reported to result in fatal renal toxicity.
- Absorption of tetracyclines is impaired by antacids containing aluminum, calcium or magnesium and preparations containing iron, zinc, or sodium bicarbonate.
- Concurrent use of tetracycline may render oral contraceptives less effective.
DOSAGE AND ADMINISTRATION:
250-500mg every 6 hours preferably 1 hour before or 2 hours after meals. Higher doses ,up to 4g daily, have occasionally been given to adults with severe infections,but increase the risks of adverse effects.It is also sometimes given orally with other tetracycline derivatives