Atonic seizure: recognising a sudden loss of muscle tone

It is sometimes called a drop seizure or drop attack. Because loss of tone can happen without warning, injury from striking the floor or nearby objects may be more obvious than the seizure itself.

The eyelids or head may droop, an object may fall from the hand, the knees may buckle, or the whole body may go limp. Awareness can be briefly impaired, and the person may recover quickly but feel weak or need help standing.

Fainting, heart rhythm problems and other events can also cause sudden falls. Diagnosis depends on a detailed witness account and may involve neurological examination, brain-wave recording and other tests chosen for the individual. A first unexplained drop should not be self-diagnosed.

If you can do so safely, guide the person away from stairs, traffic, water and sharp edges. Cushion the head after a fall, loosen tight clothing around the neck, check breathing and stay nearby until normal awareness returns. Note what happened and how long the event lasted.

Do not restrain the person, put anything in their mouth or give food, drink or tablets until they are fully alert. Follow their written seizure action plan and give rescue medicine only if you are trained and the plan directs it. Frequent unpredictable falls may require clinician-guided protective headgear and changes to the home environment.

Call emergency services for a first suspected seizure, serious injury, breathing difficulty, an episode in water, repeated seizures without recovery, or failure to return to the person's usual state. An event lasting five minutes or longer also needs emergency help unless a specialist action plan gives different instructions.

Urgent assessment is also appropriate when a sudden drop occurs with fever, stiff neck, severe headache, pregnancy or possible poisoning. Do not let the person drive themselves for evaluation.

Ask which details or video would help identify the event, whether a seizure action plan is needed, how to reduce fall injuries, what medicine effects to watch for, and which activities such as bathing, swimming, heights or driving require specific precautions.