A very good boundary is: I will not allow my home to be a detox center.
But, if you insist on playing Florence, first things first. If there are children in the home, get them out for at least 3 or 4 days. Send them to camp, to grandma’s, to a trusted friend, anyplace away from what could become a house of horrors.
If he’s coming off large amounts cold-turkey, make sure you have a blood-pressure cuff as spiking blood pressure during withdrawal can be fatal. Make sure you have a bag packed and your cellphone fully charged just in case those not so fun hallucinations occur. Don’t hesitate calling 911 if things get out of hand.
Other than that, have puke buckets, Imodium AD, diluted Gatorade, lots of Charmin, Pedialyte strips, clean sheets, chicken broth, and various weight blankets on hand. And, expect him to irritable x 10, so you will be walking on eggshells. Sounds fun, huh?