As far as I can tell, the maximum approved daily dose of Viagra is 100mg. If a 150 lb man takes that, you're looking at about 1.5 mg/kg/day, which is an eighth

As far as I can tell, the maximum approved daily dose of Viagra is 100mg. If a 150 lb man takes that, you're looking at about 1.5 mg/kg/day, which is an eighth of what they gave the rats in this study. If I'm reading this other study (http://informahealthcare.com/doi/abs/10.1080/004982599238687 http://informahealthcare.com/doi/abs/10.1080/004982599238687) correctly, we could probably roughly triple the equivalent dose in rats to account for their more rapid clearance of sildenafil. So we're still looking at 2-3 times a large dose for humans, taken over an extended period of time. So we can reason right off the bat that this is an atypical use case. Glancing at experience reports on the internet, it appears pretty rare for people to exceed 100 mg doses, and even rarer for them to keep using it day after day for a week at a time. The one segment of the population we might expect to approach the level of usage tested in this study would be male porn stars. That's a group that is probably concerned more with building muscle than losing weight, so it seems unlikely that they'd be in a position to notice that particular effect.