Theodore Dalrymple was a prison psychiatrist who dealt with thousands of addicts. In this clip he says the physical effects of giving up heroin are "trivial".
https://www.youtube.com/watch?v=7MTmpbVgn7s
This is a quote from a summary of his book “Junk Medicine: Doctors, Lies and the Addiction Bureaucracy” :
"Almost everything you know about heroin addiction is wrong. Not only is it wrong, but it is obviously wrong. Heroin is not highly addictive; withdrawal from it is not medically serious; addicts do not become criminals to feed their habit; addicts do not need any medical assistance to stop taking heroin; and contrary to received wisdom, heroin addiction most certainly IS a moral or spiritual problem."
Here's a review of the book :
https://www.telegraph.co.uk/culture/...ut-heroin.html