These categories equate to some 30% of all inquiries made. The breakdown was in the order: stimulants (4.5%); OTC fever and pain treatments (3.4%); allergy/anti-histamines (2.6%), for all queries made. Numbers of inquiries about PDE-5 inhibitors were on par with those about antibiotics, painkillers

and alcohol. Given the population (young athletes), the proportion of interest in PDE-5 inhibitors appears to be above the level that would normally be expected for medical reasons. The main medical reason for such drugs, erectile dysfunction, in men below 40 years of age is very low (< 3%) [22] and only increases with chronic medical conditions (e.g. diabetes, severe obesity) or learn more tobacco smoking – none of which is expected to be prevalent in the highly trained, competitive athlete group. Figure 3 Number of inquires grouped by class between January 2006-June 2008. As shown in Figure 4, the total number of enquires about Viagra® type substances per month is comparable between the two year period to 2008 and during the first six months of 2008. Among queries that match the database (i.e. “”found”") small shifts in numbers are seen in the Combretastatin A4 purchase latter period in favor of sildenafil and tadalafil, with minute losses against

their brand names Viagra® and Cialis®. A group of compounds identified as nitric oxide precursors were identified and monitored. These include (organic) nitrates, nitric, nitric oxide, NO2® or NO-Xplode®. NO2® appears on supplement distributor and bodybuilding web sites and is described as nitrite.

In contrast, for nitric oxide related searches a three-fold increase in queries was observed despite the absence of these 4-Aminobutyrate aminotransferase names on the database. In trends: the monthly average for the nitric/nitrate groups has steadily MRT67307 increased from 2.6% (2006) to 4.6% (2007) to 6.5% (2008). Thus, there has been a growing interest in nitrite related agents in contrast to a stable number of inquiries regarding Viagra® type agents leading up to the Beijing Olympics. Figure 4 Number of vasodilator related queries during 2006-2008 by category as A) “”found”" and B) “”not found”". Evidence from queries made to the DID™ along with sports internet discussion boards identifies a growing interest in blood enhancing agents including Viagra® and nitric oxide based agents. A particular concern is the promotion of these drugs among athletes as performance enhancing supplements. Many athletes will be unaware of the potency and side effects associated with their abuse. In particular, sodium nitrite, the nitric oxide precursor, has led to fatalities. In a recent event, sodium nitrite was mistakenly used as salt for food preparation and led to two reported coma cases and four deaths [23], which highlights the toxicity at small doses that can occur outside of clinical supervision.