Small blisters (blisters) running on legs may be caused by herpes simplex, eczema, shingles, etc., which need to be treated with medication and physical therapy. 1. Herpes simplex: herpes simplex on legs will have small blisters and running water. For patients who have herpes simplex can use antiviral drugs such as acyclovir and vasiclovir under doctor’s guidance, or apply 3% acyclovir ointment and 1% pentoxifylline ointment locally. If secondary infection occurs locally, antibiotic ointment such as fusidic acid cream and mupirocin ointment should be applied. 2. Eczema: legs long small blisters running water is also considered to be caused by eczema, the patient needs to follow the doctor’s instructions with 3% boric acid solution, 0.1% of the solution and other topical solution, such as wet compresses. In addition, some patients can also be under the guidance of the doctor with tretinoin cream, mometasone furoate cream and other glucocorticoid ointment coated in local treatment. For patients with more serious symptoms, you can take oral cetirizine, loratadine and other antihistamines as prescribed by the doctor. 3. Herpes zoster: when herpes zoster appears on the legs, there will also be small blisters with symptoms, patients need to be under the guidance of the doctor with vaxilovir, famciclovir, acyclovir and other antiviral drugs. In addition, some patients can be treated with low-energy helium-neon laser therapy to promote the blisters to subside. Small blisters on the legs running water is also considered to be contact dermatitis, insect bite dermatitis and other causes, the patient needs to consult a doctor to check the cause of the disease, to follow the doctor’s instructions to choose the appropriate measures for treatment.