 [ Symptoms ] what type of seizure last for about 16 to 20 minutes [ Disease ] well let me start by noting that not all body shaking is caused by a seizure seizures are caused by abnormal brain signals while other types of involuntary body movement such as tremors may be hereditary and of unknown origin there also are different types of seizures some of them involve mild to severe convulsions but some of them merely cause a person to sort of stare off into space for awhile as if they can not hear you seizures rarely dare i say never last up to 20 minutes most seizures last just a few minutes maybe 3 to 5 minutes or so before they end if you believe you have had a seizure you should see a doctor for further examination and assessment it is important to do this because a seizure can be a symptom of another underlying health problem such as in infection i hope this helps it is because i am a survivor of one i have epilepsy from several head injuries and in 2012 minutes after surgery for a lumbar laminectomy i had a documented +30 minute seizure which ended with having a 4 day stay in icu along with scaring a surgeon and a anesthesiologist even with all the precautions a 6 hour stay ended up with a 4 day camping trip at one of my least favorite places luckily i do not remember anything except for the usual aura headaches and tiredness after each seizure what saved my life was communication asking questions and family and doctor support meds i take keppra and depakote