<prompt> Drug of choice for pneumocystis carinii is:DoxycyclineCotrimoxazoleTetracyclineDapsone  <response>: Answer is B Cotrimoxazole: Trimethoprimsulfamethoxazole or Cotrimoxazole is the drug of choice for all firms of Pneumocystis Pneumonias. Trimethoprim-Sulfamethoxazole which acts by inhibiting folic acid synthesis is considered the drug of choice for all forms of Pneumocystis Pneumonias. Therapy is continued for 14 days in Non-HIV-Infected patients and for 21 days in HIV-Infected patients - Harrison 18th1672 