Urushiol, is the rash-causing oil found in all parts of poison ivy, poison oak, and poison sumac plants. Approximately 85% of the population experiences an allergic reaction to these noxious plants, and according to the National Institute of Occupational Health & Safety, 50 micrograms of urushiol is enough to cause a rash in 80-90% of adults.
Sweaty palms, more properly known as palmar hyperhidrosis, is a condition that affects about 1% of the US population. Although the exact cause of sweaty palms is still debated, many experts believe it is caused by a hyperactive sympathetic nervous system, causing the sweat glands in the hands to produce sweat unnecessarily.
Secondary Hyperhidrosis Causes. Sweating from secondary hyperhidrosis is different from primary hyperhidrosis in that it tends to happen all over or in one general area instead of on the hands, underarms, face, or feet. Unlike primary hyperhidrosis, this type is more likely to cause sweating during sleep. And in this case, there is something thatâs causing hyperhidrosis: a medical condition or a medication. A number of medical conditions have the potential to cause hyperhidrosis.