I recall there was a thread where the issue of side effects were discussed. For me, even 5 mg of tadalfil gives me a nasty headache for a day and a half. Never tried sildenafil but I am experimenting with vardenafil that's been in my stash. Whether 5, 10 or 20 mg, I experience a mild headache, nasal congestion and dyspepsia. Do side effects with the aforementioned drugs or this particular drug eventually decrease or even disappear, particularly the headache and dyspepsia? Took 20 mg this morning and after 4 hours, just side effects. I'm aware, too, that all of those drugs call for physical stimulation for them to work. I've read some men claiming the contrary. That's some men, and they might be exceptions. In the clinical trials of Viagra, when it was being researched as a medication for coronary artery disease, men taking it got spontaneous erections. Stop the presses!!! It would be so convenient to take a pill, but not if I'm going to feel lousy for a day. Thanks.