Generalized tonic seizure 2010-07-10T03:03:51Z Characterized by a sudden increase in muscle tone whereby the body, arms, or legs make sudden stiffening movements and consciousness is usually preserved. Tonic seizures can occur during sleep. Tonic seizures usually affect both sides of the body, and cause a fall if the affected person was standing when the seizure started. Generalised tonic seizure UMLS:C1836508 Generalised hypertonic seizure Hypertonic seizures Generalized tonic seizures A generalized tonic seizure is a type of generalized motor seizure characterized by bilateral limb stiffening or elevation, often with neck stiffening without a subsequent clonic phase. The tonic activity can be a sustained abnormal posture, either in extension or flexion, sometimes accompanied by tremor of the extremities. Generalised tonic seizures HP:0002184 HP:0010818 Generalized hypertonic seizure Generalized-onset motor seizure Tonic seizure