Hello, with reference to your query that convulsions are involuntary spasms especially those affecting the full body. The symptoms include body twitching, body spasms, jerking limbs, head spasms, facial spasms, fits, bladder incontinence, bowel incontinence, and loss of consciousness, sleeping after convulsion. It may vary from person to person. There are 5 different types: Febrile convulsions, caused by fever in infants, Grandmal's seizures in epilepsy. Petit mal seizures (often in children), Focal seizures and Generalized seizures. The main causes are: Fever, epilepsy, breath holding, whooping cough, brain inflammation, meningitis, encephalitis, head injury, stroke, brain tumor, hypoglycemia, poisoning, drug overdose, alcohol withdrawal, occupational lead exposure, chemical poisoning, rabies, plant poisoning, magnesium deficiency and so on. Treatment depends on the underlying cause like paracetamol, thiopental, and phenobarbitone. Regarding your query about the possible drug that could have been given to result in the death for certain may include so many drugs; rather it is difficult to pinpoint any particular drug. Any drug that is over dosed can result in death. Hope this helps. Thank you.