Is it possible to show a shellfish allergic reaction on the penis? I ask because I ate shrimp like an hour ago, i took a shower n once I got out of the shower I noticed a rash all over the head of my penis. This ism't the first time it's happened. It's only at times itchy, but not much. No bleeding or discharge. I am 26 n even though I've been sexually active since I was 18, I've never really had sex. Just a lot of bjs, etc. But i've never put my penis in a vagina or anus. To my knowledge, my sexual partners have been clean. I do have high blood pressure, which I take Internol (atenolol) for. I am 6'2" n weigh 210lbs. I don't regularly workout but do keep active. I am allergic to kiwi. It's just been recent that I have been getting redness n slight itchiness, but I have had some sort of rash in the past. It's as though sometimes I get chaffing(sp?) Because it sometimes occurs after a long bj, or from masturbation. Know it's a various part question, sorry.