Robert asked
I take Viagra and am getting an odd side effect. I feel like I can't breath well after taking it due to congestion. I am usually fine before hand. Is this from the medication?
Answer
It is very possible that Viagra could be causing your nasal congestion.
A well known side effect of the PDE5 medication class (which includes Viagra, Cialis, Levitra etc.) is in fact nasal congestion. Viagra and drugs like it work by inhibiting an enzyme known as Phosphodiesterase-5, or PDE5 for short. Phosphodiesterase is a broad class of enzymes found all over the body. Inhibition of PDE5 by drugs like Viagra produce a vasodilation of blood vessels which helps facilitate blood flow. Unfortunately, PDE5 inhibitors aren't solely selective for the PDE5 enzyme. They affect other PDE enzymes as well. It is thought that the nasal congestion you are experiencing is due to the inhibition of a PDE enzyme that dilates blood vessels in the nose.
In addition to nasal congestion, people report disturbances with smell as well. The nasal congestion and disturbances with smell should go away once the drug is out of your system, so you don't have to worry about lasting effects. Taking Sudafed (Pseudoephedrine) might also help with any congestion you are experiencing.
