“The chemical causes penile blood vessels to dilate and increases blood flow into the penis,” explains Dr. Laurence A. Levine, a urologist in Chicago. As a result, cGMP builds up in the penis and encourages a more sustained blood flow.
So how does that affect the refractory period? (Also… what is the refractory period?)
The refractory period is the fancy science name for the time between blowing your load and being able to go again. Per Levine, “There’s no clear defined science, but the understanding is that there’s a period of time after which a man ejaculates where another erection cannot occur and separately where the man wouldn’t be able to experience an orgasm and ejaculate again.” It is, in other words, one of those things that isn’t studied too often, so there are few definitive facts on why it happens, how long it lasts or what it’s for.
What we do know is that this period can be reduced by the same little blue pill that lets you get it up for round one in the first place. “The erectile refractory period can be shortened by Viagra,” Levine confirms. “That is to say, if a man is on Viagra and ejaculates, with restimulation of the penis, he will be able to obtain a satisfactory erection to engage in sex more quickly than if he was not on it. Sometimes it can be right away, or minutes later.”
Well, ####. This is news! How does it work?
In scientific terms, Levine says, “All that’s needed to keep an erection is the previously noted ‘good chemical,’ cGMP, which causes the blood vessels to dilate. This chemical is broken down by PDE5 (let’s call this the ‘bad chemical’), but Viagra blocks the effect of PDE5, so more cGMP is around to stimulate blood vessel relaxation.”