The clinical pharmacology of intranasal l-methamphetamine.
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.


CONCLUSIONS
Inhaled l-methamphetamine delivered from a non-prescription product produced minimal effects but may be a cardiodepressant.
Mendelson
John E
JE
Addiction 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
McGlothlin
Dana
D
Harris
Debra S
DS
Foster
Elyse
E
Everhart
Tom
T
Jacob
Peyton
P
Jones
Reese T
RT
D000281:Administration, Intranasal; D000328:Adult; D001682:Biological Availability; D001794:Blood Pressure / Q000187:drug effects; D001831:Body Temperature / Q000187:drug effects; D004452:Echocardiography; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008694:Methamphetamine / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000652:urine; D008875:Middle Aged; D010147:Pain Measurement
D008694:Methamphetamine