Painkillers cause insomnia...currently it's my life. I wound up in the ER last week due to crashing from lack of sleep, close to 3 days straight, among other issues.

So if your dad has been on an opiate or is coming off of them then insomnia can be a side effect. Generally dr's will prescribe Ambien (evil side effects for me) Lunesta and then something like a benzodiazepine (lorazepam, clonazepam etc..) I've been on em all really, amitryptaline, trazadone, benzos...I don't see them working well for me at all. Last night to finally get to sleep I took trazadone, lunesta and clonazepam, not sure if that was safe but at that point I didn't care.

any of those drugs listed above you can ask your dr about to see if they'll help

Be Well

Eric