Herpes simplex, an acute viral infection of the skin characterized by one or more painful, itching blisters filled with clear fluid. It is caused by either of two herpes simplex viruses: Type ...

Herpesvirus, any of the family (Herpesviridae) of common DNA-containing viruses, many of which are associated with human disease. See cytomegalovirus; Epstein-Barr virus; herpes simplex; herpe...

Neuralgia, acute paroxysmal pain along a peripheral sensory nerve. Unlike neuritis, there is no inflammation or degeneration of nerve tissue. Neuralgia occurs commonly in the area of the facia...

Skin patch, transdermal patch, or transdermal delivery system, adhesive patch used to deliver a controlled dose of a drug through the skin over a period of time. A skin patch uses a special me...

Antiviral drug, any of several drugs used to treat viral infections. The drugs act by interfering with a virus's ability to enter a host cell and replicate itself with the host cell's DNA. Som...

AIDS or acquired immunodeficiency syndrome, fatal disease caused by a rapidly mutating retrovirus that attacks the immune system and leaves the victim vulnerable to infections, malignancies, a...