title: Return to activity at altitude after high-altitude illness.
abstract: BACKGROUND
  Sports and other activities at high altitude are popular, yet they pose the unique risk for high-altitude illness (HAI). Once those who have suffered from a HAI recover, they commonly desire or need to perform the same activity at altitude in the immediate or distant future.
  
  
  METHODS
  As based on key text references and peer-reviewed journal articles from a Medline search, this article reviews the pathophysiology and general treatment principles of HAI.
  
  
  RESULTS
  In addition to the type of HAI experienced and the current level of recovery, factors needing consideration in the return-to-play plan include physical activity requirements, flexibility of the activity schedule, and available medical equipment and facilities. Most important, adherence to prudent acclimatization protocols and gradual ascent recommendations (when above 3000 m, no more than 600-m net elevation gain per day, and 1 rest day every 1 to 2 ascent days) is powerful in its preventive value and thus strongly recommended. When these are not practical, prophylactic medications (acetazolamide, dexamethasone, salmeterol, nifedipine, or phosphodiesterase inhibitors, depending on the type of prior HAI) may be prescribed and can reduce the risk of illness. Athletes with HAI should be counseled that physical and mental performance may be adversely affected if activity at altitude continues before recovery is complete and that there is a risk of progression to a more serious HAI.
  
  
  CONCLUSIONS
  With a thoughtful plan, most recurrent HAI in athletes can be prevented.
authors.affiliation: Uniformed Services University of the Health Sciences, Bethesda, Maryland.
authors.forename: Kevin
authors.initials: K
authors.lastname: Deweber
authors.forename: Keith
authors.initials: K
authors.lastname: Scorza