How Did I Get a Hot Tub Rash?

Ever left a hot tub at a friend’s house or hotel spa only to develop a mysterious rash sometime after? Maybe what was once a mildly annoying itch turns far more serious: red bumps might start appearing on your skin only to spread as you scratch. Odds are that you have a little bit of what is colloquially known as hot tub rash.

Not so easy to pronounce, you likely have a case of hot tub folliculitis—a common condition caused by a bacteria known as pseudomonas. Bacteria and other microorganisms (fungi, viruses, etc.) love to breed in warm, damp places, making a hot tub an ideal breeding location. Sanitizers in your water are meant to kill anything that shouldn’t be growing there and to provide a safe soaking environment but if it isn’t properly maintained, these kinds of nasty side effects can manifest themselves.

People often mistake folliculitis as an allergic reaction to the sanitizer used in hot tubs (most commonly chlorine, bromine, or biguanide). While that kind of reaction is possible, it’s much more likely to have gotten an adverse reaction to the bacteria that causes folliculitis.

Hot tub folliculitis is known as a Recreational Water Illness (RWI) and is caused when the hair follicle becomes inflamed or infected due to bacteria. It causes small reddish bumps or an itchy rash, something that sufferers may first mistake for a bug bite. The rash usually shows up approximately 24-72 hours after exposure.

Bumps often develop in areas where bacteria-ridden water is trapped underneath a swimming suit. Children are often susceptible because they are known to stay in hot tubs or pools longer than adults and they also tend to leave their suits on long after they’re done swimming—a practice that may aggravate the problem. One way to help prevent it is by rinsing right after leaving a pool or hot tub and getting out of wet swimwear immediately. You should then proceed to adequately wash and dry your suit.

Hot tub rash generally clears up on its own as long as you aren’t scratching and helping it spread. If it has persisted or even worsened after a week, it may be time to visit your doctor. In severe cases, it may require antibiotics to help clear up. There are a few ways you can soothe the itching and prevent spreading from home:

1)    Wash the affected areas twice a day with a mild antibacterial soap.

2)    Use a warm compress to reduce swelling and promote draining. This will also make it itch less.

3)    Make compress by running a washcloth under warm water and squeezing out, applying directly to the rash.

4)    Dermatologist Dr. Debra Jailman suggests using a compress of half white vinegar, half cool water for 15 minutes, twice a day.

5)    Use an over-the-counter hydrocortisone cream to relieve additional itching and inflammation.

6)    Make sure you monitor the rash closely and call your doctor if the rash spreads or you have increased swelling.

A huge reason this bacteria becomes present in the water in the first place is a breakdown of proper sanitation. Whether you’re using a bromine or chlorine system, it should be sufficient enough to keep bacteria at bay. If you’re hoping to keep these microscopic pests out of the water, here are a few steps you can take to ensure that:

1)    Test your water often using test strips or test kits to maintain proper pH, alkalinity, and sanitizer levels.

2)    Shock your hot tub water at least once a week, more during times of heavy usage.

3)    Before doing a routine refill, use a purge system to help clear out any errant water from the plumbing before filling the system back up.

4)    Refill your water every four months, using a pre-filter to help balance the water initially.

5)    Make sure your filters are cleaned often and that you aren’t getting any buildup that would lend itself to bacteria growth. Use a filter cleaner to make sure they are getting sufficiently sanitized.

6)    Maintain your spa cover. Mold can grow on these if not properly maintained and can contribute to unhygienic hot tub water. If your cover has been become waterlogged or damaged, you may need to invest in a new one.

If you get a hot tub rash, you can hopefully diagnose it, treat it, and prevent it from happening in your own hot tub. After all, it’s meant to be a means of relaxation, not infestation! Happy soaking!