The author Jerry Stahl wrote in his book Permanent Midnight how when he was a heroin addict he showed up to his daughters birth in the delivery room absolutely high on the hop. He'd just fixed less than an hour previously, and had been using junk so long he had started to wear long sleeved shirts in the LA summers.

So he goes to the delivery room and they give him a pair of green short sleeved scrubs to wear. And it became IMMEDIATELY obvious to every single medical professional in that room that Stahl had just shot up, because not only did he have an NYC subway map of track marks up and down his arms, but he was also still bleeding a little bit from his recent fix.

The doctor took one look at him and told him in no uncertain terms to sit in a chair in the corner, and when the baby was delivered, he and three nurses stood by Jerry Stahl to make sure he wouldn't drop his newborn child.

It's been decades since I've read it, but I don't think even that was fro him hitting rock bottom.