Propecia and other big name meds inhibit DHT production. However they do have side effects (can make you inpotent which would defeat the whole purpose).
I never tried any of the big name ones for that reason, but from the more natural drugs that I have tried, the only one that has every worked for me has been
Saw Palmetto. This is actually not very expensive and it's over the counter. Make sure you get one that is at least 400-500 mg. I think it's better if you even go higher but for me the 500 mg is fine.
Also drink green tea. It seriously works. I'm a big tea drinker so for me the switch from black to green tea wasn't hard.
I see what you're saying, but the big name drugs are a google search away anyway. Propecia and Rogaine have commercials on TV, but I don't think they're over-the-counter so he would have to see a doctor first even if he decides that. I wouldn't recommend it with all the side effects.
My opinion: male patter hair loss is about genetics and it can't be stopped, BUT it can be delayed.
sltn: good diet (cut the sugar and alcohol), 7-8 hrs of sleep min, and natural meds like saw palmetto. Add vitamins if you like. And green tea (we're all tea drinkers so might as well drink the type that's all benefits).