Sores or blisters on the lips or mouth or in the throat are usually caused by one of two conditions. One is an infection by the virus herpes simplex; the other is a condition called aphthous ulcers, whose cause is unknown. Aphthous ulcers are open sores that may look like herpes simplex sores, occurring in [...]

The following is a list of national resources, selected either because they run information hotlines or because they publish newsletters. These organizations sometimes change their telephone numbers. If you call and get a message that the number is not in service, try directory assistance. For 800 numbers, the directory assistance number is 1-800-555-1212. AIDS Clinical [...]