To determine the feasibility of primary care-based ambulatory opiate detoxification (AOD) and an optimal regimen, the authors conducted a pilot study of AOD in a medical clinic comparing two regimens: clonidine and clonidine plus naltrexone. Sixty-two opiate addicts who had been referred for AOD had the following features: mean age was 34 years, 75% were male, 74% used cocaine, and 64% shared needles. Initially, 40 patients selected clonidine, 22 clonidine/naltrexone. The groups (clonidine and clonidine/naltrexone) were similar in baseline features, including: craving scores (44/100 vs. 42/100) and withdrawal scores (20/72 vs. 17/72). Overall, 61% (38/62) of initial AODs were successful, including 43% (17/40) of those using clonidine and 95% (21/22) of those using clonidine/naltrexone (p less than 0.0001). Of 45 patients who ultimately completed AOD, 78% (35/45) remained in treatment for at least one month.