• Definition

    Convulsions are when a person's body shakes rapidly and uncontrollably. During convulsions, the person's muscles contract and relax repeatedly.

    The term "convulsion" is often used interchangeably with "seizure," although there are many types of seizures, some of which have subtle or mild symptoms instead of convulsions. Seizures of all types are caused by disorganized and sudden electrical activity in the brain.

    See also:

    • Epilepsy
    • Fever (febrile) convulsions in children
    • Generalized tonic clonic seizure
    • Partial (focal) seizure
    • Petit mal (absence) seizure
    • Seizure


    Convulsions can be unsettling to watch. Despite their appearance, most seizures are relatively harmless. They usually last from 30 seconds to 2 minutes. However, if a seizure is prolonged, or if multiple seizures happen and the person doesn't awaken in between, this is a medical emergency.

    If a person has recurring seizures, and no causes can be identified, that person is said to have epilepsy. Epilepsy can usually be controlled well with medication.

    Pay attention to:

    • Which arms or legs are shaking
    • Whether there is any change in consciousness
    • Whether there is loss of urine or stool
    • Whether the eyes move in any direction

    • Alcohol use
    • Barbiturates, intoxication or withdrawal
    • Brain illness or injury
    • Brain tumor (rare)
    • Choking
    • Drug abuse
    • Electric shock
    • Epilepsy
    • Fever (particularly in young children)
    • Head injury
    • Heart disease
    • Heat illness (see heat intolerance)
    • Illicit drugs, such as angel dust (PCP), cocaine, amphetamines
    • Low blood sugar
    • Meningitis
    • Poisoning
    • Stroke
    • Toxemia of pregnancy
    • Uremia related to kidney failure
    • Very high blood pressure (malignant hypertension)
    • Venomous bites and stings (see snake bite)
    • Withdrawal from benzodiazepines (such as Valium)