What happens during an atonic seizure?

Reviewed by Yoshinori Abe, MD

Internal Medicine

An atonic seizure, also known as a "drop attack," is a type of seizure where muscles suddenly lose strength and tone. This causes the person to go limp, their head to drop, or their body to collapse briefly. Atonic seizures typically last less than 15 seconds, and the person usually remains conscious throughout the episode.

Because atonic seizures can look similar to fainting, cataplexy, or other neurological events, identifying the cause of sudden collapse can be challenging. If you or a loved one has experienced unexplained episodes of muscle weakness or collapse, understanding your symptoms is a critical first step toward getting the right diagnosis and treatment. Take a free, instant, online symptom check to explore possible causes and confidently navigate your next steps with your healthcare provider.

Reviewed for medical accuracy: 07/20/2026

Important Next Steps

Discover if your seizures need care today Learn likely causes of seizure-like episodes Find out if it could be epilepsy See OTC options for seizure recovery support Find a neurologist for seizure evaluation Discover safe home remedies after seizures Understand if seizure events need urgent care

Not seeing your question? No worries.

Submit your own Question

Explanation

Atonic seizures, sometimes called "drop attacks," involve a sudden loss of muscle control. Key points include:

Muscle weakness: Muscles suddenly relax, leading to a loss of posture or collapse. Duration: These seizures are usually very brief, lasting only a few seconds. Consciousness: The person may remain awake but may also lose consciousness briefly. Risk of injury: Because of sudden falls, there is a risk of injury, so safety precautions are important. Recovery: After the seizure, muscle strength returns quickly, but the person may feel weak or tired for a short time.

If you're experiencing unexplained muscle weakness or sudden loss of muscle control, try Ubie's free AI symptom checker to help identify possible causes and guide your next steps. Atonic seizures require medical evaluation and treatment to reduce risks and improve safety.

(References)

Kovac S, & Diehl B. (2012). Atonic phenomena in focal seizures: nomenclature, clinical .... Seizure, 22789404.
Scholly J, Bartolomei F, Valenti-Hirsch MP, Boulay C, De Saint Martin A, Timofeev A, et al. (2017). Atonic seizures in children with surgically remediable .... Epileptic disorders : international epilepsy journal with videotape, 28832003.
So NK. (1995). Atonic phenomena and partial seizures. A reappraisal. Advances in neurology, 8848976.

Thinking about asking ChatGPT?Ask me instead

Tell your friends about us.

We would love to help them too.

For First Time Users

What is Ubie’s Doctor’s Note?

We provide a database of explanations from real doctors on a range of medical topics. Get started by exploring our library of questions and topics you want to learn more about.

Was this page helpful?

Purpose and positioning of servicesUbie Doctor's Note is a service for informational purposes. The provision of information by physicians, medical professionals, etc. is not a medical treatment. If medical treatment is required, please consult your doctor or medical institution. We strive to provide reliable and accurate information, but we do not guarantee the completeness of the content. If you find any errors in the information, please contact us.