Methadone is a painkiller and fairly common. Chloral hydrate is a sleep medication, a sedative, no longer used much by “modern” doctors.
Marilyn Monroe had just changed from her addictive sleeping pill of choice, Nembutal, to Chloral Hydrate, when she was found dead.
Whatever. Reading Google, I’m not going to understand. Don’t want to, maybe. I take asprin and not much of that.