Many opiate users entering prison require medication to aid detoxification. A study carried out at Leeds prison found buprenorphine to be significantly more effective than dihydrocodeine at producing opiate-negative urine samples at five days. 'The study supports the result of an earlier sister trial in the community in which buprenorphine was a more effective detoxification agent than dihydrocodeine. When choosing prescribed detoxification support in either community or secure environments GPs should not routinely use dihydrocodeine. GPs need to be aware of the high rate of relapse to opiate use following prison-based detoxification.'