Prior to the onset of hypothermia the body maintains a relatively stable temperature whereby heat production is balanced by heat loss. When the outside environment gets too cold or the body's heat production decreases, hypothermia occurs (hypo=less + thermia=temperature).
The main symptom of poison oak, ivy, or sumac is an intensely itchy, red rash. ... However, you should contact a doctor right away if you are highly sensitive or have the following symptoms: Swelling of the face or throat; Rash on the genitals; ...
In severe cases of poison ivy, poison oak, or poison sumac, it is a good idea to see a doctor. Sometimes large blisters need to be drained and sometimes an oral steroid such as prednisone may be useful. Systemic steroids produce rapid resolution of both the itching and the rash.