buprenorphine and Miosis

Nineteen heroin-dependent male volunteers were administered buprenorphine sublingually, in ascending daily doses of 2, 4, and 8 mg. They were maintained on 8 mg daily through study day 18. On study days 19 through 36, subjects in group 1 continued to receive burprenorphine daily; subjects in group 2 received buprenorphine or placebo on alternate days. On days 37 through 52, all subjects received placebo. Subjects receiving buprenorphine on alternate days reported significantly greater urge for an opioid, increased dysphoria scores, and pupillary dilation on placebo days. After abrupt termination of buprenorphine, no withdrawal signs were detected with the Himmelsbach scale. However, subjects reported mild-to-moderate opioid withdrawal symptoms, peaking at 3 to 5 and lasting for 8 to 10 days. Daily administration of buprenorphine provided greater control of subtle opioid withdrawal symptoms, but subjects could tolerate a between-dose interval of 48 hours.

Topics: Adult; Behavior; Buprenorphine; Drug Administration Schedule; Female; Heroin Dependence; Humans; Male; Middle Aged; Miosis; Sleep; Substance Withdrawal Syndrome

Pupillometry and ocular response measures are sensitive to a variety of acutely administered drugs and as such are useful for drug detection and fitness-for-duty applications. The utility of pupillometry to complement urine testing in methadone clinics, where there is considerable non-therapeutic drug use, has not been tested. A video-based pupillometer (FIT 2000) was evaluated in 37 opioid-maintained patients. Three times a week they provided urine samples and pupillometry measures of: initial diameter (ID) in mm; constriction amplitude (CA) in mm; constriction latency (CL) in msec; and saccadic velocity (SV) in mm/sec. Analysis of the success rates indicated that 92.9% of subjects obtained an acceptable reading, 59% on the first attempt. Low variability in pupillary parameters on drug-free days are necessary for effective identification of concomitant drug use. The variability (standard deviation) of ID (0.51 vs. 0.68), CA (0.12 vs. 0.27) and SV (7.2 vs. 11.1) increased on days when the urine was positive for abused drugs compared with drug-free urine days in subjects (n = 6). Subjects who were always drug-free (n = 4) had lower variability than those who always had urine positive for additional drugs (n = 20). These preliminary results suggest that pupillometry may be useful to verify concomitant drug use in a methadone-maintained population. Successful implementation of the methodology could reduce costly and intrusive urine testing.

Topics: Adult; Biometry; Buprenorphine; Diagnostic Techniques, Ophthalmological; Drug Interactions; Female; Humans; Illicit Drugs; Male; Methadone; Miosis; Opioid-Related Disorders; Pupil; Reflex, Pupillary; Substance Abuse Detection

The pupillary effects of intravenous buprenorphine were studied in eight nondependent male subjects who reported previous opiate use. Buprenorphine (0.3, 0.6, and 1.2 mg) decreased pupil size, the amplitude of the light reflex, and the velocities of constriction and dilation. Significant pupillary effects occurred within 15 min of the injection and persisted for 24 hr. At 48 hr most measures returned to baseline levels. Generally the magnitude of the effect was not dose related although recovery occurred sooner after the lower dose. The time course of the pupillary effects of buprenorphine exceeds duration of its analgesic and subjective effects. Previous studies have reported that pupillary measures are especially sensitive to the acute effects of full opiate agonists. The results of the present study indicate that buprenorphine, a partial opiate agonist, causes profound and persistent effects on pupillary size and dynamic measures.

Topics: Adult; Buprenorphine; Humans; Injections, Intravenous; Kinetics; Male; Miosis; Pupil; Reflex, Pupillary