When people come in contact with poison ivy, the urushiol can cause an allergic skin reaction that produces reddish, itchy, and painful inflammation of the skin (dermatitis). Close relatives of poison ivy plants that produce similar dermatitis symptoms are poison oak and poison sumac.
Health conditions that may cause excessive sweating include: 1  Diabetes. 2  Endocarditis. 3  Fever of undetermined cause.  Generalized anxiety 1  disorder. Hiatal hernia.  Heat 1  exhaustion. HIV/ 2 AIDS. Hyperhidrosis.  Hyperthyroidism (overactive 1  thyroid) 2  Leukemia.  Malaria.
What Causes Head Sweating? In some cases, excessive head sweating can be caused by certain medications, or an underlying condition such as a thyroid problem, and so it is important to seek a medical opinion for any excessive sweating, especially if it is a new problem.