Hmm weird, I never had this problem and could go for 30-45 min with ease when I first started having sex, before becoming a huge opiate addict. Opiates made me go for an ungodly time like 2-4 hours, almost too long, like someone is getting sore too long lol.
Now when I'm off opiates I cum in like 3-5 min when I masterbate, don't know how it would be during sex..
I don't know where I'm going with that.. I guess if you have a hookup for vicoden/hydrocodone or other opiates you could take a moderate dose like an hour or so before sex and go for an hour or two.. and the sex should be great, more intimate.
If your not into opiates try busting a nut before you have sex. Its proboly not as effective as taking an opiate but its cheaper and u don't need drugs. thats what the guys on "Loveline" would suggest when people would call in complaining of premature ejaculation, they called it "taking the bullet out of the chamber" haha. So I guess its a good method, one of the guys on the show is a doctor, Drew Pinksy..
Generally masterbating more should build up your tolerence to coming and make your thang less sensitive to stimulation.