Is solar urticaria dangerous?

Usually not: Solar urticaria normally results in hives after sun exposure that is often accompanied with itching, burning, and rarely pain. Severe attacks are RARE but can manifest with malaise, light-headedness, nausea, bronchospasm, and/or syncope. If you have solar urticaria, I recommend taking an oral antihistamine about an hour before going outdoors and protecting your skin when outside.