Epilepsy was diagnosed in our 19-year-old daughter five years ago, but she hasn't had a seizure for more than a year. The recent reports that John Travolta's son may have died after an epileptic-type seizure have obviously worried us. How dangerous is epilepsy?

Epilepsy doesn't have any impact on life expectancy for most of the British population - 1 in 50 - who develop the condition at some stage, but it can bring some additional risks, particularly for those with the more serious form of the disease.

Around 500 people with epilepsy die every year in the UK from a poorly understood complication known as Sudden Unexpected Death in Epilepsy (Sudep). There is generally no clue as to why someone has died from Sudep, but one theory is that severe seizures - particularly those that occur at night - interfere with the part of the brain that controls breathing. So normal breathing never resumes after the victim loses consciousness.

Fortunately, it is extremely rare in the vast majority of people with epilepsy whose condition, like your daughter's, is well controlled. But it is an appreciable risk (around 1 in 200 a year) in those who struggle to control their seizures and /or don't take their medication properly. It's one reason why it is vital that people with poorly controlled epilepsy are properly reviewed by a consultant neurologist.

Obviously if you have the type of epilepsy that causes you to lose consciousness without warning (and not all do), then that can carry additional hazards too, but these are much smaller than generally thought. With a bit of careful planning, they shouldn't stop people enjoying potentially “hazardous” activities such as swimming (never swim alone, etc).

The UK National General Practice Study followed nearly 800 people with epilepsy over a 14-year period, during which there were five deaths related to the condition (from Sudep or injuries sustained after a loss of consciousness). Perhaps more reassuring was that most of the volunteers tracked over the 14 years went into remission and had stopped having seizures.

Your daughter's epilepsy is under control and her future is as bright as that of any teenager.

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