A tonic-clonic seizure is frightening, but a single, brief seizure is usually not dangerous to the person having the seizure and never dangerous to anyone else except perhaps if the person is caring for a baby or driving a car. If the person has a definite history of tonic-clonic seizures, it is rarely necessary to visit the emergency room or doctor's office after a seizure unless there is evidence or suspicion of an injury or if the seizure was unlike previous ones. If this is the person's first tonic-clonic seizure, however, a prompt consultation with a doctor is essential. A person with epilepsy should wear a medical-alert bracelet or necklace that gives the person's diagnosis, medications, telephone numbers of the doctor, and the person to call in case of an emergency. It can help avoid unnecessary actions or costs if a seizure occurs in a public place. MedicAlert (www.medicalert.org; 888-633-4298) is a nonprofit organization that provides bracelets, necklaces, and cards with important medical information. The organization has a 24-hour emergency response center, which provides a source of information for emergency medical personnel. MedicAlert will also call family contacts to let them know of an emergency.

Prolonged, continuous, or repetitive tonic-clonic seizures require urgent medical attention. The patient is best transported to a medical facility by ambulance, as he or she may need oxygen, and a convulsion in a passenger car can be dangerous for everyone involved. How long does a seizure have to last to warrant a call for help? There is no absolute answer. This issue is worth discussing with the doctor. In general, if the actual convulsion lasts more than 5 minutes, or if the need for assistance is uncertain, it is best to call for help.

Topic Editor: Steven C. Schachter, M.D.
Last Reviewed:12/15/06