Proscar is by far and away the most popular drug treatment for enlarged prostate. Even so, its manufacturer, Merck, is said to be frustrated at the relatively slow take-up of a drug it regards as ground-breaking.
Many specialists seem less than impressed, mainly because it takes between three and six months of usage before symptoms improve and, if they do, it seems to happen only in a small minority of patients.
The drug has not fared much better in clinical trials, with the placebo ("sugar pill") alternative proving just as effective in the short-term, at least.
Although Merck says the drug can effectively reduce the size of the prostate, patients have complained that urine flow has not improved, and so cannot see any noticeable benefits.
But if the beneficial effects seem difficult to pin down, the side effects are better documented. In a trial of 543 patients, seven had to stop the treatment because of adverse reactions. Side effects can include sexual problems, such as impotence and decreased libido, breast tenderness and enlargement, and skin rash and lip swelling.
The greatest danger posed by Proscar is not, however, for men, but for women, particularly if they are pregnant or may become so while the man is taking the drug. If she is pregnant, she should not touch crushed Proscar nor should she have unprotected sex as the semen may contain the drug, which could damage the male fetus. Children should also be kept well away from the drug.
Before Proscar treatment is started, doctors are advised to give BHP (benign prostatic hyperplasia) patients a digital rectal examination first.
So it could be a case of pain with no gain.