I have chronic sleep disorder. prescriptions don't work i started taking 200 mgs dephenhydromine, and it really works. is this too dangerous?

Depends on situation: The recommended dose is 50mg up to every 4 hours this antihistamine (benedryl) has been around for a long time & is the active component of most otc sleep products. It crosses into the brain & interferes with neurotransmitters. Various people can develop a tolerance to the med & need more, some will have weakness, hallucinations or seizures at such a dose. It is a drug & it can hurt you.