I can achieve and erection. but have trouble having an orgasm. most times i do not have one?

Many factors!: First, as all men age, the frequency of being able to have an orgasm decreases, much more so than erectile ability. Also, a number of drugs, including beta-blockers, thiazide diuretics, sris (prozac), will also block the ability to attain an erection. Also, frequent sex will hinder the ability to achieve an orgasm. I cannot tell which and any of my comments apply to you! always talk to your doc!

Get checked: Can be psychological, realtionship related or a hormonal imbalance.