A common rash pediatricians see is called "hot tub folliculitis". The rash appears most commonly on the areas where some one's swimsuit covered. It appears as small to larger pimplish bumps and sometimes other small red bumps. One can have a few or hundreds of these bumps. It usually breaks out in 2-5 days after the initial irritation.
The hair follicles can become clogged with oil from our skin or sunscreen. Exposure to changing temperatures, as with getting in and out of a pool or hot tub, make the follicles open then close -- potentially clogging these follicles.
The rash may cause no symptoms or can cause itching or mild pain. Many children do not seem to be bothered by the rash. The rash may fade on its own over a few days. If the itching or discomfort are more troublesome, a mild antibiotic ointment or hydrocortisone cream may be used. Occasionally, with worse inflamed-looking pimples, an antibiotic by mouth is needed.
To avoid hot tub folliculitis, these things are all helpful: 1. Shower before you enter a pool or hot tub. This helps clean off the germs and oils on your skin, making hot tub folliculitis less likely. 2. Take a shower after being in the pool or hot tub. Get out of the swimsuit soon after being in the water and get into clean clothes. If you have plugged your pores while being in the water, getting out of your swimsuit, showering, and getting into clean clothes will make it less likely the you will end up with folliculitis.
If your rash is larger pimples, very itchy, getting worse, or something you have other questions or concerns about, call your pediatrician's office during regular business hours.