Hyper Plus Male Enhancement Nitric oxide levels decrease as men age and it is one of the most frequent causes of impotence and a weak erection. To increase production naturally, you can take the herbs Ginseng, Horny Goat Weed, and Cnidium that naturally stimulate production by providing you with the nutrition you don't get in your everyday food. Within a few weeks, most men find that erections are noticeably harder and last longer.