The Authors Reply

We thank Windsor and colleagues (2011) for commenting on our recent publication in High Altitude Medicine and Biology, in which ergogenic effects of dexamethasone on mountaineers prone to high altitude pulmonary edema (HAPE) are reported (Siebenmann et al., 2011). The authors raise concerns about health implications of prolonged dexamethasone administration and also address ethical considerations regarding drug-related performance enhancement. They underline their viewpoint by citing a case report describing severe side effects of more than three weeks of dexamethasone intake in a climber at Mount Everest (Subedi et al., 2010).

We agree that the case described by Subedi and colleagues clearly illustrates how drugs for prevention and treatment of high altitude illness should not be used. However, it was not the aim of our study to prove the efficiency of dexamethasone as a prophylaxis against altitude illness. We rather aimed to investigate how the impact of dexamethasone on the pulmonary circulation affects hypoxic exercise capacity in individuals likely to present with subclinical HAPE and thereby further elucidate the physiologic mechanisms that limit exercise performance at altitude. The decision to start the medication prior to the altitude exposure was based on the experience that a later onset may not be effective (Naeije & Melot, 1990).

For prevention of high altitude diseases slow ascent should always be the first precaution. However, despite slow ascent, symptoms and signs of high altitude illness may still appear in susceptible persons. It is only for these mountaineers that acetazolamide and nifedipine or a phosphodiesterase-5-inhibitor are recommended for prevention of acute mountain sickness (AMS) or HAPE, respectively (Luks & Swenson, 2008). Although dexamethasone has been found effective for the prevention of both conditions, it should merely be considered a rescue treatment for severe AMS and/or high altitude cerebral edema (HACE) and, in combination with a pulmonary vasodilator, for HAPE.

Certainly, it is tempting to use dexamethasone as a drug to decrease the risk of high altitude illness while ascending and profit at the same time of its ergogenic impact. However, given its potential side effects if taken over a long period of time (as the above cited case report demonstrated), it should not be used in this perspective just to reach desired summits. Nevertheless, in our experience, subjects receiving dexamethasone up to a maximum of 5 days never presented with side effects with the exception of a slight increase in blood glucose level (Maggiorini et al., 2006).

Windsor and colleagues also raise ethical concerns about drug-related performance enhancing and compare the use of dexamethasone to doping in sport competitions. However, in times when oxygen masks and pre-installed fix-ropes are standard to improve safety in high altitude mountaineering, the use of drugs for the prevention of high altitude illness does not appear unethical. Regarding the ergogenic effects, it is, outside of competitions, left to an individual person to decide whether an artificial performance enhancement should be considered cheating or not. It is a climber's own decision to use unfair means while climbing mountains. We as physicians can only discourage it.