Shingles can only occur after someone has had chickenpox. However, people who have not had chickenpox could become infected with herpes zoster and develop chickenpox. They should avoid contact with the shingles rash or with any materials that may have touched the shingles rash or blisters. Both famciclovir and galaciclovir are taken three times each day, compared to five times for acyclovir. All of these drugs work best when they are started within the first three days after the shingles pain begins.
Doctors often prescribe various pain medications for people with shingles.
Because the pain of shingles can be so intense, some researchers have looked for other ways to block the pain. When the herpes zoster virus inflames nerves, they pump out a chemical messenger called glutamate. Glutamate then lands on receptors on nearby cells, which transmit pain signals to the brain. Shingles triggers such a flood of glutamate that some cells stop functioning while others become hypersensitive. This probably explains why shingles patients can feel great pain even when skin is touched only lightly.