Diseases & Conditions

With in-depth information about common medical concerns and their significance to divers, Diseases & Conditions entries cover anatomy, epidemiology, symptoms, prevention, first aid and more. Implications for diving are included for the diver, dive operator and physician.

If you could not find an answer to your question or want to learn more, call us on the DAN Medical Information Line at +1 (919) 684-2948.

View and search all of DAN’s Diseases & Conditions posts here.

Immersion Diuresis

The urge to urinate is common in diving, even among divers who don’t usually need to urinate frequently. The explanation is rooted in dive physiology. The phenomenon is known as immersion diuresis, and it occurs whenever the body is immersed in water. Immersion, along with cool water temperature, causes narrowing of the blood vessels in […]

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Asthma and Diving

More than 25 million Americans — including some divers — have asthma. If the disease is well managed and the individual has good lung function and exercise tolerance, a doctor trained in dive medicine may approve of diving.

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Diabetes and Diving

A DAN study on diabetes and diving monitored plasma glucose levels in divers with and without diabetes. The findings of this study offer insights into the effects of diving on blood glucose and considerations for divers with diabetes.

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Decompression Illness

Decompression illness (DCI) encompasses two conditions: decompression sickness (DCS) and arterial gas embolism (AGE). Symptoms of DCI include numbness and tingling, pain in the joints or muscles, fatigue, dizziness, shortness of breath and more.

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Flying After Diving

Flying after diving can increase the risk of decompression sickness (DCS) because of the relative decrease in ambient pressure with altitude. Here’s how to lower your likelihood of DCS and ensure your safety during your next flight.

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Anxiety: Is It a Contraindication to Diving?

Anxiety is a mental health condition that refers to an overwhelming sense of apprehension or fearfulness. Anxiety can produce both psychological and physical symptoms that may be relevant in diving.

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Hypertension is a common medical condition in both the general population and among divers. Hypertension affects people differently, and not everyone knows they have it. Certain medications may have implications for diving.

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High-Pressure Ophthalmology

Diving exposes the eyes to increased pressure. While most of the time this has little or no negative effects on the diver, problems are possible. Learn more about how cataract surgery, glaucoma and other eye-related concerns may affect diving.

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Mask Squeeze (Facial Barotrauma)

Failure to properly equalize the air space in your mask may result in an injury to the face and/or one or both eyes. Common among new divers, this condition can be avoided with attention to equalization while diving.

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Motion Sickness

Motion sickness, or seasickness, can happen to anyone. When the inner ear sends signals to the brain that differ from those sent from the eyes, this can lead to dizziness, nausea and vomiting. Fortunately there are many options for managing the condition.

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Middle-Ear Equalization

Middle-ear equalization is an essential skill for divers. Understanding how pressure changes affect the air spaces in your ears and sinuses will aid your understanding of how the various equalization techniques work.

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Middle-Ear Barotrauma (MEBT)

Middle-ear barotrauma (MEBT) is common in diving, but with proper precautions it can be avoided. Learn the symptoms, prevention strategies and proper first aid techniques for this troublesome underwater ailment.

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