Brief Answer:
Usually calamine is not used for Herpes rash.

Detailed Answer:
Hello and welcome,

The armpit would be a very unusual place to have a rash caused by Herpes Simplex. Usually that affects the area either around the mouth or genitals or anus.

But Herpes Zoster, which causes both chicken pox and shingles can happen anywhere, including the armpit. It causes a painful blistering type of sore that then scabs. And Valtrex, which you are on, can help decrease the overall pain and duration.

Is Shingles what you are dealing with?

Regarding the calamine, I don't think it will do very much, and it's drying effect may make the sores more irritated.

Instead, clean gently with mild soap and water and apply petroleum jelly (Vaseline) if you want to put something on it to soothe it. Some studies indicate petroleum jelly may aid healing of the sores.

I have had Shingles and I know it can be miserable. I hope this information helps you and you have a quick recovery.

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