Antiviral drugs are a class of medication used specifically for
treating viral infections. Like antibiotics for bacteria,
specific antivirals are used for specific viruses. Unlike most
antibiotics, antiviral drugs do not destroy their target
pathogen; instead they inhibit their development. Antiviral
drugs are one class of antimicrobials, a larger group which also
includes antibiotic (also termed antibacterial), antifungal and
antiparasitic drugs. They are relatively harmless to the host,
and therefore can be used to treat infections. They should be
distinguished from viricides, which are not medication but
deactivate or destroy virus particles, either inside or outside
the body. Antivirals also can be found in essential oils of some
herbs, such as eucalyptus oil and its constituents. Most of the
antiviral drugs now available are designed to help deal with
HIV, herpes viruses (best known for causing cold sores and
genital herpes, but actually the cause of a wide range of other
diseases, such as chicken pox),