Effect of Acetazolamide on Central Sleep Apnea Related to Opium Consumption

This is a double-blind, placebo-controlled, cross-over designed study to evaluate the effect of acetazolamide on central apneas in opium-user patients. We are going to invite 12 eligible patients to enter our study. this sample will be obtained from the referral patients to Masih Daneshvari hospital sleep Lab. Eligible patients will undergo a full night polysomnography (PSG) to have a new measure of apnea indexes as baseline. Epwoth Sleepiness Scale Questionnaire (ESS) will be filled by the patient the night of the study.also an arterial blood sample will be obtained at the morning of each study. if the patient have more than 5 central apneas in each hour he/she will be scheduled to randomly receive a box containing 6 capsules to use one hour before bedtime at coming nights. The prescriber physician who will also score the tests and the patients are unaware either these capsules are acetazolamide 250mg or placebo. at 6th night we will perform PSG together with ESS questionnaire and arterial blood gas (ABG). after 2 weeks washout the patient receive another box containing 6 capsules with similar appearance to previous ones. If the patient receives acetazolamide in the first six nights, he/she will receive placebo in the second phase of the study and if the patient receives placebo in the first phase, he/she will receive acetazolamide in the second phase. after the second 6 days, the third PSG will be performed plus ESS measurement and morning ABG sampling. Coded polysomnograms will be scored blindly.