The most effective form of drug addiction treatment consists of using a long acting substitute and slowly tapering off.

The most common cause of overdose deaths is quitting cold turkey as people end up taking more of the drug to compensate the withdrawal.

I don't think you lose much tolerance within the week or so the acute withdrawal symptoms last.

I think the danger is from relapses long after withdrawal when both tolerance and knowledge of the supply has been lost. In some ways, withdrawal is the easy the bit - brutal but something to fight that gets easier as time passes. The nagging empty hole in your soul with sobriety is harder to fill and drags you back.