Most heroin users with access to cheap medical grade heroin (medical grade heroin is cheap - we know this because it's in use in healthcare; e.g. the UK NHS prescribes it under the generic name diamorphine for a variety of uses, including post-op pain - in hospital only - in some cases) are perfectly able to carry on with their lives - and hold down jobs. With heroin as with most drugs the criminalisation is what is causing most - not all - of the harm.