Drug Groups

approved; investigational

Description

A synthetic tetracycline derivative with similar antimicrobial activity. Animal studies suggest that it may cause less tooth staining than other tetracyclines. It is used in some areas for the treatment of chloroquine-resistant falciparum malaria (malaria, falciparum). [PubChem]

Indication

Doxycycline is indicated for use in respiratory tract infections caused by Mycoplasma pneumoniae, Haemophilus influenzae, Streptococcus pneumoniae, Legionella spp., or Klebsiella spp. It is also used for prophylaxis of malaria. Doxycycline is indicated for a variety of bacterial infections, from Mycobacterium fortuitum and M. marinum, to susceptible E. coli and Brucella spp. It can be used as an alternative to treating plague, tetanus, Campylobacter fetus

Pharmacology

Doxycycline, a long-acting tetracycline derived from oxytetracycline, is used to inhibit bacterial protein synthesis and treat non-gonococcal urethritis and cervicitis, exacerbations of bronchitis in patients with COPD, and adult periodontitis.

Toxicity

Symptoms of overdose include anorexia, nausea, diarrhoea, glossitis, dysphagia, enterocolitis and inflammatory lesions (with monilial overgrowth) in the anogenital region, skin reactions such as maculopapular and erythematous rashes, exfoliative dermatitis, photosensitivity, hypersensitivity reactions such as urticaria, angioneurotic oedema, anaphylaxis, anaphyl-actoid purpura, pericarditis, and exacerbation of systemic lupus erythematosus, benign intracranial hypertension in adults disappearing on discontinuation of the medicine, haematologic abnormalities such as haemolytic anaemia, thrombocytopenia, neutropenia, and eosinophilia. LD₅₀=262 mg/kg (I.P. in rat).

Affected Organisms

Biotransformation

Hepatic

Absorption

Completely absorbed following oral administration.

Half Life

18-22 hours

Protein Binding

>90%

Elimination

They are concentrated by the liver in the bile and excreted in the urine and feces at high concentrations in a biologically active form.

References

External Links