PubMed Health⌕ Search

Biomedical subjects

M L Stitzer

Publications and source records attributed to M L Stitzer.

At least 73 records · Page 4Linked to original sources
PubMed1994

Outcome after methadone treatment: influence of prior treatment factors and current treatment status.

Post-treatment follow-up assessments were conducted on patients from a clinical trial examining the efficacy of different doses of methadone. The Addiction Severity Index (ASI) was administered at treatment entry and ten weeks after the six-month program. Patients were improved in drug and alcohol use, and in areas of pro-social behaviors, at the time of follow-up. Improvements were not related to in-treatment variables, but were related to resumption of treatment during the follow-up interval. These results demonstrate improvement persists after methadone treatment, and further improvement can be achieved by resumption of further treatment.

Adult↗
PubMed1994

Contingent methadone take-home doses reinforce adjunct therapy attendance of methadone maintenance patients.

Two studies utilized within-subjects designs to determine whether take-home methadone doses can reinforce adjunct therapy attendance of drug abuse patients. These studies varied the reinforcement density and the schedule of methadone take-home doses. In Study 1, patients (n = 10) either could or could not receive a take-home following each therapy session. Study 2 patients (n = 15) could either earn take-homes following each therapy session attended (i.e., 2 take-homes per week) or could earn one take-home dose following each attendance to two consecutive sessions attended. In both studies experimental conditions alternated during three-week blocks of time. Across studies, any reinforcement by take-home doses produced more attendance at therapy sessions than that observed in the no reinforcement condition. Take-home incentive effects were strongest when each of the two weekly therapy sessions was reinforced by a methadone take-home dose. Increased attendance was not associated with reduced drug use, due perhaps to high rates of pre-study drug use and limited therapy duration. Contemporary opioid abusers present with multiple problems that methadone was never intended to treat. The present studies illustrate a method by which methadone treatment can improve the likelihood of delivering other services that may prove effective in treating some of these problems.

Adult↗
PubMed1994

Clinical pharmacology of buprenorphine: ceiling effects at high doses.

OBJECTIVE: The purpose of this study was to characterize the acute effects of buprenorphine, an opioid partial mu-agonist, across a wide range of doses in comparison to methadone. METHOD: Healthy adult male volunteers, who had experience with but were not physically dependent on opioids, participated while residing on a closed research unit. Four subjects received buprenorphine (0, 1, 2, 4, 8, 16, and 32 mg sublingually and five subjects received methadone (0, 15, 30, 45, and 60 mg orally) in ascending order at 1-week intervals. Physiologic, subjective, and behavioral measures were monitored for 96 hours after drug administration. RESULTS: Both drugs produced typical opioid agonist effects (positive mood, sedation, respiratory depression, and miosis), some of which persisted for 24 to 48 hours. A plateau was observed for the dose effects of buprenorphine on subjective measures and respiratory depression. Pharmacokinetic data revealed that plasma concentrations of buprenorphine were linearly related to dose, indicating no limits on sublingual absorption in this dose range. CONCLUSIONS: This study shows a plateau on buprenorphine effects, consistent with its partial agonist classification, and that single doses of buprenorphine up to 70 times the recommended analgesic dose are well tolerated by nondependent humans.

Administration, Sublingual↗
PubMed1994

Comparison of buprenorphine and methadone in the treatment of opioid dependence.

OBJECTIVE: This study compared the efficacy of buprenorphine and methadone in the treatment of opioid dependence. METHOD: Participants (N = 164) were relatively treatment-naive, opioid-dependent applicants to a 26-week treatment program who were randomly assigned to either methadone or buprenorphine treatment. Dosing was double-blind and double-dummy. Patients were stabilized on a regimen of either methadone, 50 mg, or buprenorphine, 8 mg, with dose changes possible through week 16 of treatment. Urine samples were collected three times a week, and weekly counseling was provided. RESULTS: Buprenorphine (mean dose = 8.9 mg/day) and methadone (mean dose = 54 mg/day) were equally effective in sustaining retention in treatment, compliance with medication, and counseling regimens. In both groups, 56% of patients remained in treatment through the 16-week flexible dosing period. Overall opioid-positive urine sample rates were 55% and 47% for buprenorphine and methadone groups, respectively; cocaine-positive urine sample rates were 70% and 58%. Evidence was obtained for the effectiveness of dose increases in suppressing opioid, but not cocaine, use among those who received dose increases. CONCLUSIONS: The results of this study provide further support for the utility of buprenorphine as a new medication in the treatment of opioid dependence and demonstrate efficacy equivalent to that of methadone when used during a clinically guided flexible dosing procedure.

Administration, Oral↗
PubMed1994

Effects of a restricted work-site smoking policy on employees who smoke.

OBJECTIVES: This study evaluated the biological and subjective consequences observed in individual smokers after implementation of a workplace smoking-restriction policy. METHODS: Employees were evaluated for 4 weeks before and 4 weeks after their workplace became smoke-free (n = 34). A comparison group of smokers whose work-site smoking was unrestricted served as controls (n = 33). Daily exposure to tobacco constituents and withdrawal effects were measured. RESULTS: Smokers at the restricted site had verified smoking reduction (mean = four cigarettes per day) and significantly reduced nicotine and carbon monoxide during the work shift. There were increases in ratings of some common withdrawal symptoms (cravings/urges, concentration difficulties, increased eating, depression). No evidence of compensatory smoking during nonwork hours was found. Overall tobacco exposure, as measured in saliva cotinine, showed a nonsignificant 15% decline. CONCLUSIONS: Workplace smoking restriction markedly altered smoking patterns (i.e., reduced daytime smoking) and reduced cotinine levels to an amount consistent with cigarette reduction. Thus, work-site smoking restriction may promote meaningful, albeit limited, reductions in tobacco exposure and consequent health risks.

Adult↗
PubMed1993

Dose-response effects of methadone in the treatment of opioid dependence.

OBJECTIVE: To compare the dose effectiveness of low to moderate doses of methadone in a sample of a contemporary population of opioid abusers, because the optimal dosing of methadone in the treatment of opioid dependence remains an issue. DESIGN: A randomized, double-blind, placebo-controlled study. SETTING: A methadone treatment research clinic. PATIENTS: Participants (n = 247) were opioid-dependent patients with a high rate of cocaine use. INTERVENTION: All participants were initially treated with active methadone for a minimum of 5 weeks and then received 15 weeks of stable dosing at 50, 20, or 0 mg per day. Individual counseling and group therapy were included. MEASUREMENTS: Treatment retention and illicit drug use as determined by intensive urine monitoring. RESULTS: Retention was better for patients who remained on active medication. By treatment week 20, retention was 52.4% for the 50-mg, 41.5% for the 20-mg, and 21.0% for the 0-mg group (50 versus 0 and 20 versus 0, P < 0.05; 50 versus 20, P > 0.05). Only the 50-mg treatment group had a reduced rate of opioid-positive urine samples (56.4% versus 67.6% and 73.6% for the 20-mg and 0-mg groups, respectively; P < 0.05) and cocaine-positive urine samples (52.6% versus 62.4% and 67.1% for the 20- and 0-mg groups, respectively; P < 0.05). CONCLUSIONS: There is a dose-response effect for methadone treatment. Doses as low as 20 mg may improve retention but are inadequate for suppressing illicit drug use.

Adult↗
PubMed1993

Opioid physical dependence development in humans: effect of time between agonist pretreatments.

We examined the effect of morphine pretreatment spacing on intensity of subsequent precipitated withdrawal response to test the hypothesis that withdrawal intensity would be inversely related to pretreatment spacing. Subjects were ten nondependent male volunteers who reported using opioids an average of 2.5 times per week. Three IM morphine injections (each 18 mg/70 kg) were administered during each of four experimental conditions. The experimental conditions involved spacing injections at 12-, 24-, 48- or 72-h intervals. Naloxone (10 mg/70 kg IM) was administered 24 h after the last morphine exposure. A comparison condition was included in which a naloxone challenge was given at 24 h following a single IM morphine pretreatment (18 mg/70 kg). Subject rated measures of symptoms and observer-rated measures of signs indicated that withdrawal intensity was inversely related to the morphine spacing interval and in particular that intensity of withdrawal precipitated after three pretreatments spaced at 12-h intervals was greater than that precipitated after a single morphine pretreatment. Physiological data supported a more intense withdrawal response in the 12-h spacing condition and provided evidence of overshoot on blood pressure and skin temperature measures. These findings are pertinent to the transition between acute and chronic physical dependence; they suggest that there is a temporal window during which repeated opioid administrations result in escalation of physical dependence but that dependence levels after widely spaced multiple exposures may be no greater than after a single exposure.

Adult↗
PubMed1993

Methadone dose and treatment outcome.

Consensus on the optimal dosing of methadone in the treatment of opioid dependence has not yet been achieved, with some programs committed to low dose regimens. This paper presents outcome results for 95 opioid abusers who remained in treatment through a stable dosing period in a double-blind fixed dose clinical trial comparing the relative efficacies of 50 (n = 44) and 20 mg (n = 34) of methadone to methadone-free treatment (n = 17). All patients showed improvements over time on measures of psychosocial functioning and psychological symptoms, emphasizing the important role of non-pharmacologic factors in methadone treatment. Furthermore, orderly dose effect relationships were seen, with patients receiving 50 mg of methadone having significantly lower rates of opioid positive urines (36% vs. 60-73%), and self-reporting a lower frequency of heroin use (3 days vs. 11-12 days per month). These results illustrate the dose-related efficacy of methadone in decreasing illicit opioid use and improving drug-related behavior.

Adolescent↗
PubMed1993

Descriptive analysis of cocaine use of methadone patients.

The increasing prevalence of cocaine use among opioid-dependent participants in methadone treatment has been documented, but there is little information about the quantity-frequency aspects of use. This study examined the cocaine use of methadone maintenance patients to determine amounts and patterns of use as well as use in combination with other drugs. Forty-five cocaine using methadone maintenance patients (78% used i.v.) reported their drug use for each day over the past 7 days after receiving information about their most recent urinalysis test results. Average reported use was 0.23 g cocaine/day on 3.4 days/week. Heroin and cocaine were typically used simultaneously, while only a subset of patients (47%) who used alcohol drank within close proximity to cocaine. Patients who used cocaine with alcohol and/or heroin on the same day (N = 28) reported more cocaine use (M = 1.0 g/week) than patients who used cocaine alone (N = 17; M = 0.49 g/week). The results suggest that methadone maintenance patients generally engage in relatively low dose cocaine use, especially when compared to non opioid dependent patients applying to cocaine treatment programs. The study further shows that patients had clear preferences for drug use combinations, which suggests that interventions for cocaine use might focus on modifying drugs used in combination with cocaine.

Adult↗
PubMed1992

Experimental model of smoking re-exposure: effects on relapse.

This study used a short-term laboratory model of smoking cessation and relapse to prospectively examine the effects of programmed self-administered smoking re-exposure during early abstinence. Sixty-seven subjects who had quit smoking for 3 days were randomly assigned either to smoke five cigarettes in their natural environment or to remain abstinent during the exposure period. The main hypothesis, that relapse to regular smoking would be quicker and more prevalent in exposed subjects, was supported. All exposed subjects had relapsed by 2 days post-exposure while 16% of unexposed subjects remained continuously abstinent throughout the 8 day study. This behavioral effect was seen in spite of acute decreases in reported desire to smoke and increases in guilt measured just after exposure. The study supports a role for stimulus re-exposure effects in the relapse process and suggests that additional research on experimental re-exposure is warranted.

Adult↗
PubMed1992

Phase-out filter perforation: effects on human tobacco smoke exposure.

Phase-Out is a mechanical device that dilutes the cigarette smoke stream by mechanically perforating cigarette filters. Machine testing of Phase-Out-treated cigarettes suggested that smoke exposure reductions of 90-95% could be achieved with the device. This study evaluated exposure to carbon monoxide (CO) and nicotine when humans (N = 10) smoked Phase-Out-treated cigarettes under controlled laboratory conditions. Using boost (i.e., change from baseline) measures of constituent exposure, reductions ranging from 30-80% were seen for both nicotine and carbon monoxide. Orderly graded reductions in constituent exposure were observed for both nicotine and carbon monoxide as the number of filter perforations increased from zero to six holes, with no further reduction at the eight-hole condition. Percentage reductions in constituent exposure generally corresponded well to those anticipated from machine testing, indicating that the controlled smoking technology was valid and that the Phase-Out device operated as expected in a human smoking assay. The utility of partial constituent-level reductions is discussed both with regard to lowered health risks of smoking and ease of quitting when partial reduction is used as a gradual weaning preparation for quit attempts.

Adult↗
PubMed1992

Contingent take-home incentive: effects on drug use of methadone maintenance patients.

This study examined contingent methadone take-home privileges for effectiveness in reducing on-going supplemental drug use of methadone maintenance patients. Fifty-three new intakes were randomly assigned to begin receiving take-home privileges after 2 consecutive weeks of drug-free urines or to a noncontingent procedure in which take-homes were delivered independently of urine test results. The contingent procedure produced more individuals with at least 4 consecutive weeks of abstinence (32% vs. 8%); 28% of noncontingent subjects also achieved abstinence after shifting to the contingent procedure. Lower baseline rate of drug-free urines was strongly associated with successful outcome, whereas the type of drug abused (cocaine vs. benzodiazepines) did not influence outcomes. Findings support a recommendation for using contingent take-home incentives to motivate abstinence during methadone maintenance treatment.

Adult↗
PubMed1992

Marijuana smoking: effect of varying delta 9-tetrahydrocannabinol content and number of puffs.

The purpose of this study was to determine marijuana dose-effects on subjective and performance measures over a wider dosage range than previously reported using technology which allowed for specification of both the volume and delta 9-tetrahydrocannabinol (THC) content of smoke delivered, and to relate these effects to plasma THC levels. Seven male community volunteers, who were moderate users of marijuana, smoked 4, 10 or 25 puffs from cigarettes containing either 1.75 or 3.55% THC on 6 separate days. Postsmoking plasma THC levels were systematically related to both number of puffs and cigarette THC content. Maximal THC levels occurred immediately after smoking and ranged from 57 to 268 ng/ml. These plasma levels provided a measure of systemic delivery when a known volume and THC content of marijuana smoke was inhaled. Orderly dose-related increases were also observed for heart rate, expired air carbon monoxide and subjective report of drug effects. The 25-puff, 3.55%-THC condition produced greater plasma THC levels than previously reported and reliably impaired performance on a battery of psychomotor and cognitive tasks with substantial individual differences noted in the degree of performance impairment. Puff number/THC content combinations producing comparable plasma THC levels resulted in similar subjective effects and performance impairment. This study provided a comprehensive assessment of the pharmacological effects of smoked marijuana over a wider and more precisely controlled dosage range than has been accomplished previously.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Effects of smoking cessation on caloric intake and weight gain in an inpatient unit.

The present research was designed to assess the amount of weight gain that would occur when male smokers in an inpatient setting were deprived of cigarettes for 10 days, and to evaluate factors that could contribute to that weight gain, such as caloric intake and activity level. Subjects were 17 healthy male smokers who either smoked ad libitum (n = 8) or quit smoking (n = 9) for 10 days after a 3 day smoking baseline. Caloric intake, activity levels, and body weight were assessed daily. Abstainers gained more weight than did smokers and ate more over time. There were no group differences in activity level. An analysis of energy needs versus actual energy intake suggests that caloric intake accounted for a large percentage of the post-cessation weight gain. However, considerable individual variability exists in caloric intake after smoking cessation. In addition, the study found post-cessation increases in caloric intake that were quite similar to those found in studies with females, suggesting that gender may have little to do with overall post-cessation caloric intake. Further research assessing dietary and metabolic changes after smoking cessation in a larger sample of both males and females is needed so that the reasons for and implications of dietary variability can be evaluated.

Adolescent↗
PubMed1991

Time course of naloxone-precipitated withdrawal after acute methadone exposure in humans.

This study examined naloxone-precipitated withdrawal symptoms from 24 to 168 h after pretreatment with a single 30-mg i.m. dose of methadone in 6 male subjects who were experienced users of opioid drugs but were not currently dependent. The study showed that acute physical dependence signs and symptoms could be reliably precipitated with a small dose of naloxone (0.75 mg/70 kg i.m.) for as long as 96 h (4 days) after a single dose of methadone. The intensity of symptoms at 24 h post-methadone was similar to that observed at 96 h; no precipitated withdrawal effects were observed at 168 h (7 days) after methadone administration. The magnitude of precipitated withdrawal effects at 96 h was not attenuated by the administration of a prior naloxone challenge at 24 h post-methadone. Agonist effects (pupillary constriction; subjective effects) were detectable at 24 h but not at 96 h post-methadone. The results suggest that methadone engenders long-lasting physical dependence effects that can be detected beyond the dissipation of acute agonist effects. Methadone pretreatments may provide a convenient mechanism for the production and examination of long-term mu-opiate receptor physical dependence.

Adult↗
PubMed1991

Acute physical dependence in humans: repeated naloxone-precipitated withdrawal after a single dose of methadone.

This paper reports the intensity and duration of acute physical dependence precipitated by naloxone administration following a single pre-treatment with the opioid against methadone (30 mg/70 kg, i.m.) in six non-dependent human volunteers with histories of prior opioid abuse. In a within-subject cross-over design, challenges of the antagonist naloxone (0.5-1.0 mg, i.m.) were administered at 6, 30 and 54 h, or at only 54 h after methadone pre-treatment. Acute physical dependence, as indicated by physiologic, subjective, and observer rated withdrawal, was seen in all subjects following active naloxone administration, was of nearly uniform intensity for a period of 6-54 h after acute methadone administration, and was not attenuated by prior naloxone administration.

Adult↗
PubMed1991

Early treatment time course of depressive symptoms in opiate addicts.

Self-reported depressive symptoms of opiate addicts were assessed at admission to a methadone treatment program and weekly during the first 4 treatment weeks using the Beck Depression Inventory. A significant decline in scores was found to occur with the first follow-up evaluation done 7 days after admission, with scores remaining stable over subsequent weeks. The study suggests that a more accurate assessment of psychiatric symptoms may be obtained by waiting 1 to 2 weeks after treatment entry as compared with admission assessments.

Adult↗