Clinical course of herpes zoster was assessed in 119 immuno-competent and in 28 immuno-compromised hosts. Complications of herpes zoster were observed in one third cases. However, the frequency of post-herpetic neuralgia was lower than that seen by other authors. Despite severe underlying diseases in compromised hosts, good outcome of herpes zoster was obtained. It may be related to the use of aciclovir in all these cases. Early and rational treatment with aciclovir is important for decreasing of the frequency of severe complications of herpes zoster.