Parallel consumption (%) of the two groups.
| Illegal heroin consumers (n = 74) | Medical heroin consumers (n = 44) | |
|---|---|---|
| Cocaine | 89.2 | 15.9 |
| Cannabis | 41.9 | 59.1 |
| Methadone | 41.9 | 34.1 |
| Benzodiazepines | 29.7 | 22.7 |
| Methaqualone | 9.5 | 9.1 |
| Barbiturates | 5.4 | 2.3 |
| Tricyclic antidepressants | 4.1 | 6.8 |
| LSD | 4.1 | 0 |
| Amphetamines | 1.4 | 0 |
| No parallel consumption | 1.4 | 18.2 |