Background}: Pharmacological therapy has an important place in the management of opioid dependence. Methadone has been the mainstay of therapy but has a number of limitations. Buprenorphine monotherapy is another option, but misuse and diversion can have negative consequences. The opioid receptor antagonist, naloxone, has been added to buprenorphine to create a combination product with a reduced potential for misuse and diversion.
Objectives: This study evaluated the use of buprenorphine/naloxone for 24 weeks as a pharmacological management of opioid-dependent patients after therapeutic switch from buprenorphine alone.
Methods: Patients (n = 43) received sublingual tablets of buprenorphine/naloxone. The buprenorphine dose was 2–24 mg (mean 16). Patients saw a physician, including an interview using a structured data sheet, and had counselling each week. Assessments were performed at week 2 (period 1), week 6 (period 2), week 16 (period 3) and week 24 (period 4). Laboratory immunoenzymatic testing was performed weekly to detect drugs in the urine.
Results: The management of withdrawal symptoms was rated as ‘satisfactory’ by 67% of patients during period 1 and 91% during period 4. The majority of patients was highly satisfied with therapy and considered that buprenorphine/naloxone provided good control of cravings. Two patients dropped out of therapy, but all others continued to receive buprenorphine throughout the study. Approximately 50% of patients stated that they disliked the sensory properties (taste, colour, odour and feel) of buprenorphine/naloxone. Adverse effects were as would be expected on the basis of the mechanism of action of buprenorphine (i.e. opioid-induced constipation) and for patients undergoing drug withdrawal. Only 2% of patients attempted the intravenous misuse of buprenorphine/naloxone, none of whom experienced any gratifying effects.
Conclusions: Opioid-dependent patients maintained on buprenorphine monotherapy can be safely switched to a sublingual buprenorphine/naloxone tablet without any loss of treatment effectiveness. Buprenorphine/naloxone can be administered in an outpatient or primary care setting, and effectively controls cravings and withdrawal symptoms. Patient satisfaction was high, making retention in treatment more likely.