Many patients with grand mal seizures have a sudden onset during sleep or in a quiet state. Patients with grand mal seizures can have generalized muscle tonic clonus, which can be accompanied by teeth clenching, foaming at the mouth, urinary and fecal incontinence, and tongue bite. When a patient has a grand mal seizure while sleeping, the airway should be kept open, the patient’s head should be tilted to the side to prevent accidental aspiration, and suffocation caused by backward tongue drop and tongue bite should be avoided. For patients with frequent seizures, sodium valproate and lamotrigine should be given to prevent seizures.