What causes heat lumps?

Question

ive never had this before but today my arms, legs and neck have been itching a lot and then forming a small lump on my skin and leaving red marks. is this heat lumps? because im worried it could be something else. i cant think what i could be allergic to because I just used a shower gel that I use everyday. i hav used cleaning products today but they have only had contact with my hands.

Answer 1

The bumps are called wheals, hives, or welts.  They are caused by allergic reactions.   Allergic skin reactions  can be triggered by all sorts of things including sweating, heat or cold, and just about anything that irritates the skin.  

Hives can also be caused by systemic reactions.  This is different from something that irritates the skin.   With a systemic reaction, the irritant is in your bloodstream and the reactions can occur anywhere in the body. The chemicals you breathe from using cleaning products can cause all sorts of reactions in some people, so that is another possibility.  Pay attention the next time you use the chemicals and see if the same thing happens again.  

Systemic reactions are a little risky because they can occur in your throat, and then block you air supply.