<s>[INST] context: TETRACYCLINES: These are a class of antibiotics having a nucleus of four cyclic rings. Tetracyclines are the first choice drugs. despite development of resistance by many organisms in: a)venereal diseases chlamydial non specific urethritis/endocervicitis: 7 day doxycycline treatment is as effective as azithromycin single dose. * Lymphogranuloma venereum: resolves in 2-3 weeks * Granuloma inguinale:Due to Calymm granulomatis: a tetracycline administered for 3 weeks is the most effective treatment. b) Atypical pneumonia: due to Mycoplasma pneumoniae: duration of illness is reduced by tetracycline therapy. Psittacosis is treated in 2 weeks by tetracyclines. &; c) cholera: Tetracyclines have adjuvant value by reducing stool volume and limiting the duration of diarrhoea. d)brucellosis: Tetracyclines are highly efficacious; cause rapid symptomatic relief; therapy of choice is doxycycline 200 mg/ day + rifampin 600 mg/ day for 6 weeks. Gentamicin may be combined with doxycycline in acute cases. e)plague: Tetracyclines are highly effective in both bubonic and pneumonic plague. They are preferred for blind/ mass treatment of suspected cases during an epidemic, though streptomycin often acts faster. (j) Relapsing fever* due to Borrelia recurrentis responds adequately. (g) Rickettsial infections: typhus, rocky mountain spotted fever, Q fever, etc. respond dramatically. Chloramphenicol is an alternative. ESSENTIALS OF MEDICAL PHARMACOLOGY K.D.TRIPATHI SIXTH EDITION PAGE NO:714,715 [/INST] question: Drug of choice for plague is: | options: A: Erythromycin B: Tetracyclines C: Ampicillin D: Cotrimoxazole | answer: B </s>