I occasionally have trouble achieving or maintaining an erection, or sometimes I will get one, but it won't be quite strong enough for penetration. Are there any effective over-the-counter supplements available at any given pharmacy? Or perhaps any foods, oils, vitamins, etc. that I should take (or avoid taking) to help promote sexual health? I can't afford the cost of prescriptions drugs at the moment (my insurance doesn't cover it), and I'm not interested in any of the fake herbal supplements they advertise on late night TV. Can anyone offer some help?