Scuba Diving and Seizure Risk
Individuals with a history of seizure disorders should not engage in scuba diving as an in-water seizure is highly likely to be fatal, even when the condition appears well-controlled. 1
Physiological Risks of Diving and Seizures
Scuba diving exposes the brain to significant physiological changes that can increase seizure risk:
- Immersion causes blood shift to the thoracic cavity, altering cerebral perfusion 1
- Nitrogen narcosis impairs cognitive function at depths beyond 30 meters 1
- Oxygen toxicity at high partial pressures can trigger seizures 1
- Arterial gas embolism can cause neurological symptoms including seizures 1
Medical Contraindications
Multiple medical authorities have clear positions on seizure disorders and diving:
- The British Thoracic Society and American Heart Association explicitly recommend against diving for individuals with seizure disorders 1
- Clinical practice standards typically prohibit diving by individuals who require continuous medication for seizure control 2
- Even with well-controlled epilepsy, the risk of seizure recurrence remains elevated for many years 3
Risk Assessment and Consequences
The consequences of a seizure while diving are particularly severe:
- An in-water seizure has an extremely high fatality risk 3
- Seizures underwater can lead to:
- Loss of consciousness
- Loss of the regulator/mouthpiece
- Aspiration of water
- Drowning
- Inability to control buoyancy
- Risk to diving companions attempting rescue
Guideline Recommendations
Different diving organizations have varying but consistently cautious standards:
- The South Pacific Underwater Medicine Society considers epilepsy an absolute contraindication to diving 3
- The United Kingdom Sport Diving Medical Committee requires individuals to be seizure-free for 3-5 years before considering diving 3
- The American Heart Association recommends a 5-year seizure-free period before engaging in scuba diving 1
Safer Alternatives
For individuals with seizure disorders who enjoy water activities, safer alternatives include:
- Swimming in shallow water with direct supervision
- Snorkeling in shallow areas with a buddy system
- Surface water sports with proper flotation devices 1
Important Caveats and Considerations
- Long-term follow-up studies show that at least one-third of people with epilepsy will have a seizure recurrence, with risk remaining elevated for many years 3
- Even if seizure-free on medication, the physiological stresses of diving (pressure changes, gas effects, cold water) may lower seizure threshold 1
- The risk is never completely eliminated, even after long periods of seizure freedom 4
The evidence strongly indicates that scuba diving presents unacceptable risks for individuals with a history of seizures, regardless of how well-controlled the condition appears to be.