People with epilepsy are not being given proper advice to help them manage their condition, a survey suggests.
One in 200 adults have epilepsy in the UK
The poll of 197 patients found half have never discussed the possible side effects of medication with doctors.
Two out of three said they were never told they may not be able to drive because of their condition.
The survey was carried out by the National Society for Epilepsy to mark National Epilepsy Week, which starts on Sunday.
About one in every 200 adults in the UK has epilepsy. There are around 1,000 epilepsy-related deaths each year.
Some people who take anti-epileptic drugs suffer side-effects. However, they are rare and if they occur they are usually mild, ranging from rashes to dizziness.
But the drugs can interact with other medication, including antibiotics and the contraceptive pill.
Anyone who has a seizure is legally obliged to tell licensing authorities in the UK. They are allowed to drive if they have not had a seizure for a year.
Women with epilepsy need to be carefully monitored by doctors to ensure their condition remains stable. Seizures can damage the unborn child and trigger a miscarriage.
However, the survey suggests doctors are failing to point out these issues to patients.
David Josephs, director of external relations at the NSE, described the findings as worrying.
"The survey has shown up some very worrying statistics in relation to lack of advice.
"There needs to be a more mature approach to discussing the risks of having epilepsy. If people don't know the facts, how can they plan their lives?"
Meanwhile, another charity Epilepsy Action has urged people with the condition to ensure they are getting the best treatment possible from doctors.
It says that 70% of people with epilepsy could become seizure free with the appropriate treatment. However, only about half currently achieve this.
"We are concerned that some people with epilepsy are not achieving the best possible seizure control," said Philip Lee, its chief executive.
"While we accept that not everyone with epilepsy could become seizure free, it may be possible for them to have fewer seizures.
"We also want to encourage people who are experiencing adverse side effects from their medication to discuss this with their doctor, to see if any improvements can be made."