When feeling unwell, the soothing heat of a hot tub offers an appealing promise of temporary relief from body aches and congestion. However, whether using a hot tub is advisable depends entirely on the specific type and severity of the illness. Since infection alters the body’s ability to regulate temperature, hot water immersion can turn a relaxing activity into a potential health risk.
The Critical Danger: Hot Tubs and Fever
The most significant safety concern involves any illness that includes an elevated body temperature, or fever. A fever is the body’s natural defense mechanism that raises the core temperature to fight infection. Immersing the body in hot water, especially near the recommended maximum of 104°F (40°C), interferes with the body’s ability to cool itself through sweating and radiation.
When the body cannot dissipate heat, the core temperature continues to climb past safe limits, causing symptoms like dizziness, lethargy, and an inability to perceive danger. A person with an existing fever will reach heat exhaustion or heat stroke much faster than a healthy individual. For safety, any temperature above 100°F (37.8°C) is a clear contraindication for hot tub use, as the risk of fainting and subsequent drowning is too great.
Mild Illnesses: Colds, Congestion, and Muscle Aches
For mild, non-febrile illnesses like the common cold, a hot tub may offer temporary symptomatic relief. The warm, humid air rising from the water acts similarly to a steam inhaler, helping to loosen mucus and ease nasal congestion. This warm vapor can reduce nasal airway resistance, making it easier to breathe for a short period.
The warmth and hydrostatic pressure from the water can also be beneficial for the muscle aches that frequently accompany a cold. This effect is due to the promotion of blood circulation and the relaxation of tense muscles. However, the heat causes vasodilation, which can lead to lightheadedness upon exiting the tub. To mitigate this risk, soak time must be limited to 10 to 15 minutes, and air circulation should be maintained.
Hygiene and Essential Safety Guidelines
If using a private hot tub with a mild, non-febrile illness, several protocols must be followed to ensure safety and hygiene. Shared or public hot tubs should be avoided entirely due to contagion risk. Proper cleaning and maintenance are necessary, and if the illness involves gastrointestinal symptoms, staying out of the water completely is necessary.
Dehydration is a significant concern, as the heat increases sweating and the illness may already be causing fluid loss. It is imperative to drink water before, during, and after the soak to replace lost fluids and electrolytes. Individuals must avoid using the hot tub after consuming alcohol or taking cold and flu medications that cause drowsiness, as this increases the risk of impaired judgment, fainting, and drowning. The soak should be abandoned immediately if symptoms like nausea, vomiting, or increased dizziness occur.