A: It is not uncommon for men to experience changes in their erectile functioning as they age. Pharmaceutical grade Yohimbe extract has worked for many men, though it shouldn't be taken alone but in combination with other helpful ingredients added. You need a doctor's prescription as this is a stronger version of what is available in a health food store. There are good herbal products on the market that have proven to be very effective and have no side affects. And of course, there is Viagra. I would suggest trying a so-called cock ring or device that simply slips over the lingam and is secured down near where the shaft meets the body. You tighten it slightly and it keeps the blood in the lingam much longer, which sustains the erection.