Everything has been tried, from herbs to horse urine to gunpowder. While some of the remedies ease the pain and itching of the dermatitis, the only thing that actually cures it is time. That said, there are some things you can do to either avoid the itch or treat its symptoms. Palliatives Palliative remedies seek to treat the symptoms of Toxicodendron dermatitis, rather than actually effecting a cure. It doesn't cure the rash, but it certainly cools and soothes the skin, if only temporarily.
Oatmeal baths can also bring temporary relief.
Interestingly, hot water can help sooth the pain for a short time. Anti-itch medications would seem to be in order, but in most cases they don't work well. Antihistamines are mostly useless, because few histamines are released at the rash site, and anything containing phenol or camphor can cause severe skin irritation. Benzocaine and related medicines may themselves cause allergic reactions. They work very well for the itching, but can cause adrenal problems, increase blood pressure, cause swelling of the face and neck, and disrupt the female menstrual cycle for months.