Fomepizole is used to counteract ethylene glycol (antifreeze) and methanol poisoning. Ethyl alcohol is sometimes used to treat ethylene glycol and methanol intoxication, but this approach has several problems because it is difficult to dose properly, causes its own profound sedating effects, and irritates veins during infusion. Hemodialysis may be the best option in severe cases if facilities are available in a timely manner. Flumazenil is a benzodiazepine receptor antagonist used to treat benzodiazepine overdose. Physostigmine can be used to treat severe anticholinergic drug toxicity. Examples of anticholinergic drugs are diphenhydramine, amitriptyline, and atropine.