A sore throat after swimming is common, often called “swimmer’s sore throat.” The discomfort is usually caused by environmental or chemical factors, not a sudden infection. The delicate mucous membranes lining the throat are highly sensitive to irritation, which can be triggered by conditions in both treated pools and natural bodies of water. Understanding these triggers helps in preventing and addressing the symptoms.
Chlorine and Chemical Exposure
The most frequent source of irritation in swimming pools is not chlorine itself but the chemical byproducts it creates. Chlorine is added to sanitize the water, but when it reacts with organic matter such as sweat, skin cells, and urine, it forms compounds known as chloramines. Chloramines are disinfection byproducts responsible for the strong odor often associated with pools, which is mistakenly thought to be the smell of too much chlorine.
Chloramines are more volatile than chlorine and readily vaporize into the air above the water’s surface. Because they are heavier than oxygen, these gases linger in the breathing zone of swimmers, especially in poorly ventilated indoor facilities. Inhaling airborne chloramines causes irritation and inflammation in the sensitive tissues of the nose, throat, and lungs. This chemical exposure can lead to a burning sensation and a dry cough, often called “chlorine cough.”
Another factor contributing to chemical irritation is the pH balance of the pool water. The ideal pH level is usually between 7.4 and 7.6, similar to human tears and mucous membranes. If the water is too acidic (below 7.0), it can directly irritate the airways, causing coughing and a dry throat. An unbalanced pH also reduces chlorine’s sanitizing ability.
Water Quality and Physical Irritation
Beyond chemical exposure, a sore throat can stem from infectious agents or mechanical stress. Poorly maintained water, whether in a pool, lake, or river, can harbor bacteria and viruses that cause infection. Waterborne pathogens, such as Cryptosporidium, Giardia, E. coli, or Norovirus, are often accidentally swallowed.
Ingesting contaminated water introduces these microorganisms, which can lead to gastrointestinal distress, flu-like symptoms, and sometimes an infection manifesting as a sore throat. While chlorine is designed to kill germs, some resilient parasites like Cryptosporidium can survive for days even in properly chlorinated water. Swimmers should avoid swallowing water in any environment to prevent illness.
Physical actions while swimming can also cause irritation unrelated to water quality. Accidentally inhaling or swallowing water can trigger a spasm in the larynx and irritate the throat and sinuses. This mechanical insult leads to temporary inflammation and soreness.
A common issue for swimmers is the drying of throat tissues from heavy mouth breathing. During strenuous exercise, swimmers often gulp air through their mouths to maximize oxygen intake, bypassing the nose’s natural function of filtering and humidifying air. This constant flow of dry air across the throat’s mucous lining leads to moisture loss. The resulting dehydration causes scratchiness or soreness that lasts after leaving the water.
Soothing the Symptoms and Prevention
For immediate relief of a post-swim sore throat, simple home remedies focus on rehydration and cleansing the irritated tissues.
- Gargling with a warm salt water solution helps soothe inflammation and rinse away residual irritants.
- Drinking plenty of non-acidic fluids, such as water or herbal tea, rehydrates the throat and helps restore the natural moisture barrier depleted by mouth breathing or chemical exposure.
- Over-the-counter throat lozenges can temporarily coat the throat and stimulate saliva production, easing dryness.
Preventing swimmer’s sore throat involves proactive steps before and during the swim. Always shower with soap before entering the pool; this reduces organic material like sweat and skin cells that react with chlorine to form chloramines. Using a nose clip stops water from entering the nasal passages and sinuses, preventing accidental inhalation and irritation. Focusing on proper breathing technique, inhaling through the mouth only as necessary, reduces the drying effect on the throat. Swimmers should avoid swallowing pool water entirely, as this is the primary way waterborne pathogens are ingested. If symptoms persist beyond 48 hours, are accompanied by a fever, or involve difficulty breathing, consult a medical professional to rule out a bacterial or viral infection.