Any form of unconsciousness under water is deadly, with the attendant likelihood of arterial gas embolism and drowning. Epilepsy, even if well-controlled, places you at great risk and one should not even consider the possibility of diving. Some years ago I worked with Dr. Jeff Davis in writing “The Medical Examination of Sport Scuba Divers,” diving guidelines for those with illnesses such as asthmatics, diabetics and epileptics. The group of doctors making those guidelines felt that all of these conditions could cause some form of unconsciousness, even though controlled nicely on the surface.
Unconsciousness under the surface at depth would be deadly and there is no such thing as a ” little seizure or spaciness” which could be tolerated, even if the person is “well-controlled on medication.” There is a clear medical risk involved and you should direct your energies and intelligence toward surface related activities. Be sure that you are advised by a doctor that is “diving aware” of the extreme dangers involved before you make any decision. The difficulty comes with the assessment of the range of severity of these disorders and the nature and effectiveness of the controlling measures.
Most diving medical people don’t feel that any one with seizure activity of any kind should be certified as ‘fit to dive’. The risks of having sudden seizure activity underwater are just too great. The regulator falls out of the mouth, there is a sudden intake of water into the lungs and the diver drowns. Compounding this is the fact that the diver then has to ascend in the water column – subjecting him/her to pulmonary barotrauma and gas embolism. (Bove, ‘Diving Medicine’, Edmonds, ‘Diving and Subaquatic Medicine’). In addition, one has to consider the increased risk placed on the diver’s buddy and other divers in the group required to rescue the individual.
A second factor which has to be considered is the nature of the drugs used to control epilepsy, which are all, to some degree, sedative in nature and would thus exacerbate nitrogen narcosis or cause it to come on at an unexpectedly shallow depth. For this reason, there are some who feel that it is considered unsafe for any epileptic to dive if he/she is currently taking any anti-epileptic medication.
It is well-known that hyperbaric conditions (chamber dive or a 60 foot water dive) can cause a low percentage of seizures in individuals who do not have epilepsy (1% in Navy studies). However, the effect of high partial pressures of oxygen on the person with controlled epilepsy is unknown.
Persons who have been seizure free for five years, on no medication who choose to dive should be advised in regard to the increased risk that hyperventilation and oxygen toxicity might precipitate seizures.
Individuals with controlled epilepsy, taking medication and seizure free for 2 years (meeting the requirements of most driving jurisdictions) are advised that if they ignore the recommendation not to dive – they have to accept the increased accident risk which is estimated to be 1.3 to 2 times that of the general population. As previously stated, this risk is also shared by diving companions, instructors, divemasters, parents and all who are directly involved.
Even so, it is interesting that these same people who are allowed to ‘drive’ are not allowed to have a pilots license – nor are they allowed to perform commercial, scientific or military diving.
References
Dreifuss FE, 1985 Epileptics and scuba diving
JAMA 253(13), 1877-1878 (1985)
[No authors listed], 1985 Should epileptics scuba dive?
JAMA 254(22), 3182-3183 (1985)
Newton HB. Neurologic complications of scuba diving. Am Fam Physician. 2001;63:2211-2218.
Hamad A, Alghadban A, Ward L. Seizure in a scuba diver. Chest. 2001;119:285-286.