Viagra, Exercise and Altitude
Viagra can improve exercise at altitude, though it is not clear if a single dose is sufficient, or if it needs to be taken regularly. It is also not clear if everyone responds to Viagra in high altitude exercise the same way. In addition, Viagra may be a treatment for altitude sickness.
1 Viagra and Performance
Viagra (the brand name for Sildenafil) has been shown to help with the effects of altitude. Some studies have shown that Viagra increases the maximum exercise capacity at altitude. One study showed that for some trained cyclists a single dose of Viagra 1 hour before exercise produced a significant improvement (39%) in sub-maximal performance in altitude (12,700 ft) while others did not experience a worthwhile improvement (1%). However, another study supplied Viagra for 6 days, and the benefits took several days to kick in. Other studies have shown benefits from a single dose 2 hours before exercise. A study of 20 male and 15 female trained athletes performing a 6 Km time trial at a simulated 12,700ft altitude showed only a single male athlete with improved performance, so individuality may be a factor.
2 Altitude Sickness
Long term use of Viagra has been shown reduce the impact of altitude. Subjects were given Viagra every 8 hours for 12 weeks inhibited a particular type of altitude sickness (high altitude pulmonary arterial hypertension or HAPH). Viagra also improved the distance the subjects could walk in 6 minutes. Altitude sickness can lead to a potentially lethal condition called "High-Altitude Pulmonary Edema" (HAPE). Viagra is considered a viable treatment for HAPE, and is being used in some situations. A review of 5 studies found that Viagra reduced pulmonary systolic arterial pressure, but did not improve oxygen saturation or Acute Mountain Sickness scores. The use of Viagra as a preventative in healthy subjects with no history of HAPE may not be justified. The best treatment for Altitude Sickness is decent, but in the event that decent is dangerous, Viagra may be useful.
3 Side Effects of Viagra
Viagra can cause headaches at altitude or at sea level. No other side effects were noted in any of the altitude studies. Viagra is a vasodilator which can cause systemic hypotension (low blood pressure), especially given with nifedipine, but a review of 56 subjects administered Viagra for altitude sickness did not have this problem.The primary use of Viagra for Erectile Dysfunction does raise some questions about other possible side effects, as well as being a source of endless jokes. However, background reading suggests that Viagra does not result in unwanted erections and requires physical or mental stimulation. In the treatment of ED, noted side effects included headache, flushing, dyspepsia, nasal congestion and impaired vision, including photophobia and blurred vision.
4 Viagra and Doping
At the time of writing, the World Anti-Doping Agency has not banned Viagra (Sildenafil), but you should check before using Viagra (or any other medication) before taking it. World Anti-Doping Agency web site.
5 What this means
Viagra is a prescription medication and should only be taken under medical supervision. I believe that self-medication is foolish and I urge you to talk to your doctor if you think Viagra would help. The performance benefits of Viagra at altitude might be significant enough to warrant further investigation, but personally I would only use Viagra as a treatment for altitude sickness.
6 See Also
- Altitude Training
- The Science of Altitude Training
- Altitude Training Approaches
- Comparison of Altitude Training Systems
- Book Review - Altitude Training and Athletic Performance
- Intermittent Hypoxic Exposure and The Science of Intermittent Hypoxic Exposure
- Chronic Mountain Sickness
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- Viagra Prescribing Information http://www.pfizer.com/files/products/uspi_viagra.pdf