Acetazolamide for the Prevention of High Altitude Illness: a Comparison of Dosing
Acetazolamide, or Diamox, is the standard medical prophylaxis agent for high altitude illness. The medication is effective in preventing acute mountain sickness (AMS), high altitude pulmonary edema (HAPE), and high altitude cerebral edema (HACE). Its mechanism is via inhibition of the carbonic anhydrase enzyme which counteracts the respiratory alkalosis which occurs during ascent to altitude. It facilitates the excretion of bicarbonate in the urine. As a result, acetazolamide hastens acclimatization and helps prevent high altitude disorders.
Current recommended dosing is 125 mg, orally twice daily, started 24 hours prior to ascending in elevation. Side effects include tingling of the fingers and toes and perioral numbness which may be erroneously interpreted as stroke symptoms. Since acetazolamide is a mild diuretic, frequent micturition may occur leading to interruption of daytime activities as well as broken sleep. These effects can affect safety at high altitude. Acetazolamide is normally discontinued 2 days after the user has reached their highest elevation or a plateau in elevation.
A lower dose may be just as effective in preventing high altitude illnesses while preventing the disconcerting side effects resulting from its use. A smaller dose has not been studied, however. We will compare the common dose of 125 mg twice daily with a lower dose of 62.5 mg twice daily.
|Study Design:||Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Treatment
|Official Title:||Acetazolamide for the Prevention of High Altitude Illness: a Comparison of Dosing|
- Prevention of acute mountain sickness as measured by the Lake Louise Score [ Time Frame: 1 year ] [ Designated as safety issue: No ]
- Side effect profile of acetazolamide [ Time Frame: 1 year ] [ Designated as safety issue: No ]The typical side effects of acetazolamide will be measured via a 1-5 scale: Paresthesias of fingers and toes, change in urination frequency, and change in taste of beverages.
|Study Start Date:||March 2012|
|Estimated Primary Completion Date:||December 2014 (Final data collection date for primary outcome measure)|
Experimental: Acetazolamide normal dose
Experimental : Acetazolamide 125 mg twice daily
Experimental: Acetazolamide low dose
Experimental: Acetazolamide 62.5 mg twice daily
Please refer to this study by its ClinicalTrials.gov identifier: NCT01993667
|United States, Utah|
|University of Utah Health Sciences Center||Recruiting|
|Salt Lake City, Utah, United States, 84132|
|Contact: Scott McIntosh, MD firstname.lastname@example.org|
|Principal Investigator: Scott McIntosh, MD|
|Principal Investigator:||McIntosh Scott, MD||University of Utah|