Cholinergic urticaria (heat hives) is a terrible condition in which the body will break out into a tingly, painful, but intensely itchy feeling when the person becomes hot, exercises, gets stressed out, nervous, or if the body temperature rises.ther symptoms of heat hives may include: 1  Red flushing during the breakout (like how your cheeks blush when you get embarrassed) on areas of the body. 2  Small hives or bumps (ranging from the size of tiny mole to the size the pupil of your eye) that may appear on the body.
Medical conditions such as thyroid disease, low blood sugar, anemia, and low blood pressure also may cause palpitations. Heart palpitations may be a sign or symptom of arrhythmia, an irregular heartbeat, or other heart conditions such as heart attack, heart failure, heart valve disease, or cardiomyopathy. Although palpitations are very common and usually harmless, they can be frightening when they happen and may cause anxiety.
Yet panic attacks and anxiety themselves do not account for all of the palpitations. 1  That's because palpitations may also occur for reasons unrelated to anxiety, but still affected by anxiety. For example: 2  Caffeine Caffeine is known to cause heart palpitations. It's likely that those with anxiety are either more prone to these palpitations, or more prone to noticing them and thus amplifying their effects. Alcohol and Nicotine Both alcohol and nicotine may also cause heart palpitations.