Tricyclic antidepressants abuse, with or without benzodiazepines abuse, in former heroin addicts currently in methadone maintenance treatment (MMT)

Background: To measure suspected abuse of the tricyclic antidepressant amitriptyline among methadone maintenance treatment (MMT) patients in Israel, we studied cross-sectionally, all our 303 patients (February, 2007). Methods: Tricyclics presence was screened in one of the random urine samples routinely taken for tests of other drugs. ASI questionnaire, variables from patients' records. Findings: 48 (15.8%) patients were positive for amitriptyline. Logistic regression (multivariate analyses) found that the extent of being amitriptyline-positive was higher in benzodiazepine (BDZ) abusers (OR = 11.6 95% CI 4.4-30.7), in subjects with positive antibody to hepatitis C (OR = 2.2, 95% CI 1.02-4.9) and in patients treated with high-dose methadone (> 150 mg/day) (OR = 2.4, 95% CI 1.2-4.9). Amitriptyline was found in 12 (7.5%) of the "privileged" group of patients (stabilized patients who, based on their long-standing cessation of any type of street-drugs abuse and prolonged normative behavior in treatment are granted "take home" methadone doses) who, by definition, should not be abusing anything. Conclusion: The high prevalence of amitriptyline abuse found in our patients, and its potential cardiac hazards when combined with BDZ abuse, emphasizes the importance of amitriptyline routine monitoring in order to decrease the potential risk associated with amitriptyline combined with methadone and BDZ, and to implement appropriate interventions.