Hot tub folliculitis, often called “hot tub rash,” is a common skin condition many people experience after spending time in warm, poorly maintained water. This infection causes an outbreak of red, itchy bumps, frequently leading people to question the safety of the hot tub itself and seek immediate solutions. A frequent question that arises is whether the process of “shocking” the hot tub water can effectively treat the resulting skin infection. While shocking is an essential procedure for sanitizing the water, it is important to understand the difference between decontaminating the environment and treating an existing medical condition on the skin.
Understanding Hot Tub Folliculitis
Hot tub folliculitis is a bacterial infection of the hair follicles that manifests as a bumpy, itchy rash. The rash often resembles acne, featuring small, red bumps or pustules centered around hair follicles, and may sometimes be tender or painful. Symptoms typically develop within a few hours to five days after exposure to the contaminated water source.
This condition is caused by the bacterium Pseudomonas aeruginosa, which thrives in warm, moist environments like hot tubs. The bacteria are resilient and can survive even in chlorinated water if sanitizer levels are low or the water’s pH is unbalanced. When a person soaks in water containing high concentrations of this bacteria, the microbes enter the hair follicles, causing the characteristic infection. The rash frequently appears in areas covered by a swimsuit, as the fabric traps contaminated water against the skin.
The Purpose of Hot Tub Shocking
Shocking a hot tub is a necessary water maintenance procedure that involves adding a high dose of an oxidizing chemical, often referred to as a shock treatment. This process, also known as super-chlorination, is designed to rapidly destroy organic contaminants in the water, such as sweat, body oils, lotions, and cosmetics introduced by bathers.
The oxidation process breaks down these organic waste materials, which otherwise consume the active sanitizer, reducing its effectiveness. Shocking also eliminates combined chlorine compounds, known as chloramines, which cause the strong chemical smell and can irritate the eyes and skin. By breaking down these contaminants, shocking reactivates the remaining sanitizer, allowing it to efficiently kill bacteria and keep the water clear and safe. Non-chlorine shocks are used for routine oxidation, while chlorine-based shocks provide oxidation and powerful sanitization.
Shocking the Water vs. Treating the Skin
The distinction between shocking the water and treating the skin lies in their respective targets. Shocking is strictly an environmental decontamination measure, aimed at sanitizing the water and plumbing of the hot tub. It eradicates the source of potential future infections by killing Pseudomonas aeruginosa bacteria living in the water.
However, shocking the water does not provide therapeutic benefit for a person who has already developed folliculitis. Once the bacteria have penetrated the hair follicles, the water treatment process cannot reach them. The high concentration of chemicals used to shock the hot tub is not a medical treatment and should not be applied to the skin. Shocking is necessary to make the hot tub safe for future use, but it offers no cure for an existing case of hot tub rash.
Medical Treatment and Self-Care
Hot tub folliculitis is a self-limiting condition, meaning mild cases often resolve on their own within seven to fourteen days without specific medical intervention. For relief of symptoms such as itching and inflammation, self-care measures are helpful. Applying a warm compress to the affected areas for fifteen to twenty minutes, several times a day, can soothe the skin. Over-the-counter hydrocortisone cream may also reduce itchiness and inflammation.
It is advisable to temporarily avoid shaving the affected area and refrain from scratching the bumps to prevent further irritation or secondary infection. If the rash persists for more than ten days, worsens, or is accompanied by systemic symptoms like a fever, professional medical attention is necessary. A healthcare provider might prescribe topical or oral antibiotics, such as a fluoroquinolone, to treat severe or persistent infections.
Preventing Future Outbreaks
Preventing hot tub folliculitis requires attention to proper water chemistry and personal hygiene. Regular testing is necessary to ensure sanitizer levels remain within recommended ranges (e.g., 3–10 ppm for chlorine or 4–8 ppm for bromine). Maintaining the water’s pH level between 7.2 and 7.8 is essential, as this range optimizes the effectiveness of sanitizing chemicals.
A consistent schedule of shocking the water is necessary to oxidize contaminants and reactivate the sanitizer, preventing the build-up of bacteria like Pseudomonas aeruginosa. After exiting the hot tub, individuals should remove their swimwear and shower immediately with soap and water. This step helps wash away bacteria lingering on the skin before they can enter the hair follicles and cause an infection.