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.
But, the most common causes include: 1  Stress hives. As previously mentioned, hives are itchy bumps on the body that can be triggered by stress. 2  Sweat rash. Anxiety also causes sweating, and sweating can lead to a sweat rash, otherwise known as a heat rash. 3  Specific triggered itch.