[maffydub]

Still true-ish - it's methadone rather than heroin.

From https://www.nhs.uk/live-well/healthy-body/drug-addiction-get...:

> If you're dependent on heroin or another opioid drug, you may be offered a substitute drug, such as methadone.

[gambiting]

No, actual, real heroin is prescribed legally to some people:

https://www.independent.co.uk/news/uk/home-news/heroin-addic...

It's also used legally in the UK in paliative care for cases where it's easier to administer than morphine.