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.
Palpitation Causes. The heart needs its normal environment to work well. This is especially true for the heart's electrical system; changes in electrical conduction may lead to a decreased ability for the heart to pump blood. From within the body, abnormal levels of electrolytes like potassium, magnesium, and calcium can cause palpitations.
Causes. Often the cause of your heart palpitations can't be found. Common causes of heart palpitations include: Strong emotional responses, such as stress or anxiety; Strenuous exercise; Caffeine; Nicotine; Fever; Hormone changes associated with menstruation, pregnancy or menopause; Taking cold and cough medications that contain pseudoephedrine, a stimulant