Methadone serum concentrations and influencing factors: A naturalistic observational study

Chalabianloo, Fatemeh; Westin, Andreas Austgulen; Skogvoll, Eirik; Bramness, Jørgen G.; Spigset, Olav

doi:10.1007/s00213-019-05277-1

Cited by 9 publications

(15 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A correlation between methadone dosage and the concentrations of methadone and EDDP found in the blood samples of study participants could not be established. This observation was also made in previous studies and can be explained by a high inter-individual variance in pharmacokinetic properties [19,20]. However, the methadone and EDDP concentrations, as well as the methadone/metabolite ratios in serum, were in the same range as those published by previous authors (3.92-53.95 (through), 4.06-30.04 (peak) [21]; 5.6-15.1 [22]).…”

Section: Discussionsupporting

confidence: 86%

Evidence for the transfer of methadone and EDDP by sweat to children’s hair

et al. 2021

View full text Add to dashboard Cite

In cases where there is a question as to whether children have come into contact with drugs, examinations of their scalp hair are frequently carried out. Positive test results are often discussed in the forensic community due to the various possible modes via which drugs and their metabolites can be incorporated into the hair. These include drug uptake by the child (e.g. oral ingestion or inhalation), but also contamination of hair via contact with the sweat from drug users. In this study, the possibility of methadone and its metabolite EDDP being incorporated into children’s hair by contact with sweat from persons undergoing opiate maintenance therapy (methadone) was examined. The transfer of methadone and EDDP via sweat from methadone patients (n = 15) to children’s hair was simulated by close skin contact of drug-free children’s hair, encased in mesh-pouches, for 5 days. Sweat-collecting patches (hereafter referred to as ‘sweat patches’) were applied to the test persons’ skin. One strand of hair and one sweat patch were collected daily from each patient. Analyses were performed using GC–MS/MS (hair) and LC–MS/MS (serum, sweat patches). After 4 days of skin contact, methadone was detectable in the formerly drug-free hair strands in all 15 study participants. EDDP was detectable in 34 of 75 hair strands, with the maximum number of positive results (11 EDDP-positive hair strands) being detected after 5 days. These results show that transfer of methadone and EDDP to drug-free hair is possible through close skin contact with individuals taking part in methadone substitution programmes. A correlation between serum concentration, sweat concentration and substance concentration in hair strands could not be demonstrated, but a tendency towards higher concentrations due to longer contact time is clearly evident.

show abstract

Section: Discussionsupporting

confidence: 86%

Evidence for the transfer of methadone and EDDP by sweat to children’s hair

et al. 2021

View full text Add to dashboard Cite

show abstract

“…At least, the clinical signi cance of the ndings may be high for the individual patient's treatment by relieving the unpleasant symptoms. Dose escalations may be considered even if the dose already given is high, keeping in mind alternations in methadone pharmacokinetics that may in uence the serum concentration reached by each particular patient [12,[14][15][16]. However, expected treatment bene ts of optimizing methadone dose must always be balanced against the risk of severe harms like death due to overdose and risk of methadone diversion [32].…”

Section: Discussionmentioning

confidence: 99%

“…Although previous ndings suggest an association between dose and clinical symptoms, the relationships between serum methadone concentration and treatment effects are still not fully understood [14]. Due to a large inter-individual variation in methadone pharmacokinetics, the individual serum concentration after a given dose will vary substantially [12,[14][15][16]. The optimal dose at steady state thus is hard to predict [12].…”

Section: Introductionmentioning

confidence: 99%

Subjective Symptoms and Serum Methadone Concentration: What Should Guide Dose Adjustments in Methadone Maintenance Treatment? A Naturalistic Cohort Study From Norway

Chalabianloo

Høiseth

Ohldieck

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

BackgroundThere is little evidence-based guidance on how to optimize methadone dosage among patients with opioid addiction undergoing methadone maintenance treatment (MMT). This study aims to investigate whether self-perceived opioid withdrawal symptoms, adverse effects and self-reported substance use in patients on MMT are related to serum methadone concentration and what role these could play in clinical decisions on dose adjustments.MethodsIn this naturalistic cohort study clinical and laboratory measurements from 83 patients undergoing MMT in outpatient clinics in Bergen, Norway during May 2017-January 2020 were included. Information on age, gender, methadone daily doses and serum concentrations, subjective opioid withdrawal symptoms (SOWS), self-reported adverse effects and substance use were obtained. Linear mixed modelling was used for analyzing the data.ResultsMean age was 45 years and 34% were women. 55% reported subjective opioid withdrawal symptoms, and all had experienced at least one subjective adverse effect. Self-reported substance use was recorded in 88% of the interviews. Total SOWS score (P<0.001), and the specific subjective withdrawal symptoms of anxiety (P=0.004), bone- and muscle ache (P=0.003), restlessness (P=0.017) and shaking (P=0.046) out of the 16 symptoms in standard SOWS questionnaire, as well as the use of heroin (P=0.015) and alcohol (P=0.011) were associated with lower methadone concentrations, whereas cannabis use was associated with higher methadone concentrations (P=0.049). Conclusions More subjective opioid withdrawal symptoms and more self-reported use of heroin and alcohol were associated with lower serum methadone concentrations. More use of cannabis was related to higher serum methadone concentrations. These findings suggest that patient's self-perceived symptoms and current clinical condition can be applied as the main guide in methadone dose adjustments. In some aberrant cases, measurement of serum concentration together with other individual assessments may be considered to support the clinical decision.

show abstract

“…Although previous findings suggest an association between the dose and clinical symptoms, the relationships between serum methadone concentrations and treatment effects are still not fully understood [14]. Due to the large interindividual variation in methadone pharmacokinetics, individual serum concentrations after a given dose will vary substantially [12,[14][15][16]. The optimal dose at steady state thus is hard to predict [12].…”

Section: Introductionmentioning

confidence: 99%

Subjective symptoms and serum methadone concentrations: what should guide dose adjustments in methadone maintenance treatment? A naturalistic cohort study from Norway

Chalabianloo

Høiseth

Ohldieck

et al. 2021

Subst Abuse Treat Prev Policy

Self Cite

View full text Add to dashboard Cite

Background There is little evidence-based guidance on how to optimize methadone dosages among patients with opioid addiction undergoing methadone maintenance treatment (MMT). This study aims to investigate whether self-perceived opioid withdrawal symptoms, adverse effects, and self-reported substance use in patients on MMT are related to serum methadone concentrations and the role that these variables could play in clinical decisions on dose adjustments. Methods This naturalistic prospective cohort study included clinical and laboratory measurements from 83 patients undergoing MMT in outpatient clinics in Bergen, Norway, from May 2017 to January 2020. Information on age, gender, methadone daily doses and serum concentrations, subjective opioid withdrawal symptoms using 16 items Subjective Opioid Withdrawal Scale (SOWS) questionnaire, self-reported adverse effects, and substance use was obtained. Linear mixed modelling was used for analyzing the data. Results The mean age of the participants was 45 years, and 33% were women. Almost half reported mild to moderate subjective opioid withdrawal symptoms, and all had experienced at least one subjective adverse effect. The use of at least one substance was reported by 88% of the participants. Serum concentration-to-dose ratios were lower among those who had reported subjective opioid withdrawal symptoms (p) = 0.039). The total SOWS score (p < 0.001); the specific subjective withdrawal symptoms of anxiety (p = 0.004), bone and muscle aches (p = 0.003), restlessness (p = 0.017), and (slightly) shaking (p = 0.046), also use of heroin (p = 0.015) and alcohol (p = 0.011) were associated with lower methadone concentrations. Cannabis use was slightly related to higher methadone concentrations (p = 0.049). Conclusions The findings suggest that the patient’s self-perceived symptoms and current clinical condition are related to the serum concentrations of methadone. This interpretation supports dose adjustments based on patient-reported symptoms. In some aberrant cases, measurement of serum concentrations together with other individual assessments may be considered to support the clinical decision.

show abstract

Methadone serum concentrations and influencing factors: A naturalistic observational study

Cited by 9 publications

References 37 publications

Evidence for the transfer of methadone and EDDP by sweat to children’s hair

Evidence for the transfer of methadone and EDDP by sweat to children’s hair

Subjective Symptoms and Serum Methadone Concentration: What Should Guide Dose Adjustments in Methadone Maintenance Treatment? A Naturalistic Cohort Study From Norway

Subjective symptoms and serum methadone concentrations: what should guide dose adjustments in methadone maintenance treatment? A naturalistic cohort study from Norway

Contact Info

Product

Resources

About