One Viagra comment I have not seen before is the following. I got 100mg pills to save money by cutting them in half.
But wow, 50mg is still too much and I weigh 180lbs. So I cut it in half again for 25mg. Still more than I needed and I still got raging headaches sometimes too. So I cut it in half again, to 12.5mg, although after that much cutting the dosage surely isn't too accurate.
So I thought that 12.5mg was good, but it makes me so hard I can easily bruise my circumsized foreskin from ordinary intercourse. The bruise goes away in a day or two and didn't really hurt, but who needs that?
Between the headaches and the bruising I think people need to be careful, and my own experience is that you really need only a minimum amount.