Social experiment: preparing a syringe with heroin in Platzspitz Park, Zurich, in 1990 Romano Cagnoni · Getty

‘I started taking heroin as a way of coping with my psychological problems,’ said David, 50, an addict for 25 years. ‘It destroyed me. I lost my job as a watchmaker. I “borrowed” money from my girlfriend, and my friends. I ended up on the street. To fund my habit, I became a user-dealer.’ Every day for 18 months, he’s been attending an injection centre attached to the Geneva University Hospitals, where, under the experimental heroin prescription programme (PEPS), he is given a syringe of diacetylmorphine — heroin manufactured legally by a Swiss laboratory. ‘The programme has allowed me to rebuild my life, and pay my friends back.’ He looked at his watch: ‘I’ve got to go. It’s time for my treatment.’

The 1,500 patients at Switzerland’s 22 PEPS centres have all tried unsuccessfully to kick their habit with drug replacement therapy. Marco, 44, said: ‘Methadone didn’t work for me. The side effects were terrible, and I didn’t get any tranquilising effect. So I was taking other drugs on top of it. I’ve been registered here for the last six months. I’ve put on weight, and cut my heroin use by 80%. Eventually, I want to get clean.’ Chantal, 54, an addict for 30 years, said: ‘The treatment gives me structure. I don’t have to chase after mydealerany more.’ Jeff, 54, had just injected his daily dose; his pupils were dilated and he spoke in a loud voice: ‘My quality of life has definitely improved. It’s stabilised my day. Before I got into the programme, I was a dealer. I was cunning, I found ways to get money, I did stuff.’

Yves Saget, an addiction nurse, said: ‘Addiction happens when taking drugs becomes the only strategy for dealing with difficult situations. We don’t say “fix” here, we say “treatment”.’ He explained: ‘The brain becomes dependent, and needs heroin to maintain its balance. At this centre, we are treating 63 patients with diacetylmorphine. Medical heroin is pure, unlike the drug you buy in the street, which is cut with caffeine, paracetamol and (...)