Herpes on the hands is usually one of two possibilities: herpes zoster or herpes simplex. In the case of herpes zoster, the main cause is that the body has been infected with the varicella-zoster virus, and under certain conditions, such as a low immune system or excessive fatigue, the nerves in the area have a certain inflammatory reaction, resulting in erythema-based blisters, which are distributed in bands and arranged along the nerves. If it occurs on the hand, it is usually unilateral and may be painful even on the arm. In the case of herpes simplex, it is mainly caused by the herpes simplex virus in the finger area, resulting in localized erythematous blisters with significant pain.