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Updated: Jul 3, 2026
A General Method for Evaluating Deep Brain Stimulation Effects on Intravenous Methamphetamine Self-Administration
Published on: January 22, 2016
The clinical pharmacology of intranasal l-methamphetamine
John E Mendelson1, Dana McGlothlin, Debra S Harris
1Addiction Pharmacology Research Laboratory, The California Pacific Medical Center Research Institute, St. Luke's Hospital, 7th floor, 3555 Cesar Chavez Street, San Francisco, CA 94110, USA. john.mendelson@cpmcri.org
Background:
We studied the pharmacology of l-methamphetamine, the less abused isomer, when used as a nasal decongestant.
Methods:
12 subjects self-administered l-methamphetamine from a nonprescription inhaler at the recommended dose (16 inhalations over 6 hours) then at 2 and 4 (32 and 64 inhalations) times this dose. In a separate session intravenous phenylephrine (200 microg) and l-methamphetamine (5 mg) were given to define alpha agonist pharmacology and bioavailability. Physiological, cardiovascular, pharmacokinetic, and subjective effects were measured.
Results:
Plasma l-methamphetamine levels were often below the level of quantification so bioavailability was estimated by comparing urinary excretion of the intravenous and inhaled doses, yielding delivered dose estimates of 74.0 +/- 56.1, 124.7 +/- 106.6, and 268.1 +/- 220.5 microg for ascending exposures (mean 4.2 +/- 3.3 microg/inhalation). Physiological changes were minimal and not dose-dependent. Small decreases in stroke volume and cardiac output suggesting mild cardiodepression were seen.
Conclusion:
Inhaled l-methamphetamine delivered from a non-prescription product produced minimal effects but may be a cardiodepressant.
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