Suffering from a dry mouth when diving is primarily the result of mouth-breathing dry, compressed air; water vapor, which usually moisturizes our breath, is removed when air is compressed into scuba cylinders. Divers using full-face masks get a reprieve because they can breathe through both the nose and the mouth. As a result, the air inside the mask is a bit warmer, but still dry and compressed. Some claim that breathing nitrox prevents dry mouth, but the air is still cold and dry. Rebreather divers have the biggest advantage since the chemical reaction that removes the carbon dioxide from the diver’s exhaled breath warms and humidifies the air.
How to prevent dry mouth when diving
Beyond the characteristics and distinctions between diving equipment, proper hydration is the first step in preventing dry mouth when diving. This may be an easy solution for most divers, as good hydration is already one of the best practices for diving. The challenge when it comes to preventing dry mouth is to be well hydrated not only while diving but also days in advance. As a reminder, ample fluids are needed to replace fluid loss from breathing dry gases and immersion diuresis. Fluids are also necessary to support bodily functions that help regulate body temperature, prevent decompression sickness, fatigue and narcosis. On diving days, begin early in the day by drinking at least ½-liter of cold water two to three hours before diving and continue to drink one liter per hour throughout the day and during diving activities. Other ways to reduce fluid loss and help prevent dry mouth are to avoid caffeine from coffee and sodas, limit alcohol and marijuana, and avoid smoking and diving.
The most popular, simple solutions for relief from dry mouth include sucking on hard candies, chewing gum, eating fresh fruit (especially citrus) between dives, drinking fluids underwater, and rinsing the mouth with water or over-the-counter remedies and mouth sprays. Some of the most interesting home remedies are rinsing the mouth with coconut oil or water and pepper, such as cayenne and placing mint toothpaste on the regulator mouth piece. More involved but preferred by some divers are moisture-replenishment systems that integrate with hoses and regulator systems, which have built-in moisture-retention design. Maintaining a good level of physical fitness helps divers develop steady, relaxed breathing patterns that may reduce the frequency of inhaling and exhaling through the mouth, which result in increased loss of fluids and contribute to dry mouth.
Medical causes for dry mouth
Dry mouth, or xerostomia (zeer-o-STOE-me-uh) is often a side effect of medications or damage to the salivary glands from illness or treatments such as radiation therapy for cancer. Dry mouth is commonly associated with diabetes, which is prevalent in the diving community. It is also a precursor to bacterial, viral and fungal infections. If dry mouth persists it is important to follow up with a physician to determine the reason and resolve it before it leads to other conditions, such as tooth decay, gum disease, bad breath or loss of taste and appetite. Solutions for these causes of dry mouth may focus more on stimulating the salivary glands. Saliva helps neutralize acids, limit bacterial growth, rinse away food, and aids in swallowing and digestion. Using CPAP machines and exercising with the mouth open can also cause dry mouth, so make a conscious effort to breathe in through the nose and out through the mouth to help prevent dry mouth when exercising.