This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
Dose of centchroman is ? 
Select and explain. 
A. 30 mg, B. 60 mg, C. 120 mg, D. 240 mg
A: 30 mg
Answer: A: 30 mg 
Explanation: Ans. is 'a' i.e., 30 mg Cetchroman (Saheli) Ormeloxifene, research product of Central Drug Research Institute, Lucknow, India. It is a potent non - steroidal compound with potent anti - estrogenic and weak estrogenic propeies. It is taken orally (30 mg) twice a week for first three months then once a week. It works primarily by preventing implantation of feilized ovum. It does not inhibit ovulation. It is avoided in PCOD, with liver and kidney diseases and in tuberculosis. There may be a tendency of oligomenorrhoea. The failure rate is 1 - 4/100 woman years of use. Failure rate is less with increased doses. It is devoid of any significant adverse metabolic effect. This may also be used as a emergency contraceptive.