Apr 18, - Redness and irritation on your penis can have other causes, too. Balanitis may occur due to infection or allergic reactions. You're more likely to get balanitis if you: sweat a lot in your genital area, creating a moist climate for bacteria, fungi, and other germs.Symptoms · Treatment · Causes. Penis problems: a visual guide. If you've got a problem down below, you really need to go to your GP or a sexual health clinic. In the meantime, here's a visual.