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Human spinal fluid methadone levels
Drug and Alcohol Dependence
|March 1, 1978
Summary
Methadone levels in cerebrospinal fluid (CSF) were measured in patients undergoing lumbar punctures. CSF methadone concentrations were a fraction of serum levels, appearing 3-8 hours after administration.
Area of Science:
- Pharmacology
- Neuroscience
- Clinical Medicine
Background:
- Methadone is a widely used opioid agonist for pain management and opioid use disorder treatment.
- Understanding methadone's distribution into the central nervous system is crucial for optimizing therapy and managing side effects.
Purpose of the Study:
- To quantify methadone concentrations in cerebrospinal fluid (CSF) relative to serum levels.
- To determine the time course of methadone appearance in the CSF.
Main Methods:
- CSF and serum methadone levels were measured in nine patients undergoing lumbar punctures for medical or surgical reasons.
- Patients were receiving methadone maintenance therapy.
Main Results:
- CSF methadone concentrations were consistently lower than serum levels, representing 2% to 73% of concurrent serum concentrations.
- Measured CSF methadone levels ranged from 0.010 to 0.097 ng%.
- Peak methadone concentrations in CSF were observed approximately 3 to 8 hours post-administration.
Conclusions:
- Methadone penetration into the central nervous system is limited and variable.
- The observed time lag suggests a delayed distribution of methadone into the CSF.
- These findings have implications for understanding methadone's central effects and informing dosing strategies.
