Which of the following is used for prophylaxis of acute mountain sickness:

Ans. C: Acetazolamide The drug acetazolamide may help some people making a rapid ascent to sleeping altitude above 2750 metres, and it may also be effective if staed early in the course of acute mountain sickness (AMS). The CDC advises that Dexamethasone be reserved for treatment of AMS and High-altitude cerebral edema (HACE) during descents, and notes that Nifedipine may prevent High-altitude pulmonary edema (HAPE). Despite their popularity, antioxidant treatments have not been found to be effective medications for prevention of AMS. Interest in phosphodiesterase inhibitors such as sildenafil has been limited by the possibility that these drugs might worsen the headache of mountain sickness