The bioavailability of intranasal and smoked methamphetamine
Debra S. Harris MD, Harold Boxenbaum PhD, E. Thomas Everhart PhD, Gina Sequeira MS, John E. Mendelson MD, Reese T. Jones MD
Clinical Pharmacology & Therapeutics 74(5), 475-486 (2003) (https://www.thevespiary.org/rhodium/Rhodium/pdf/bioavailability.intranasal.smoked.meth.pdf)
(https://www.thevespiary.org/rhodium/Rhodium/pdf/bioavailability.intranasal.smoked.meth.pdf)
DOI:10.1016/j.clpt.2003.08.002 (http://dx.doi.org/10.1016/j.clpt.2003.08.002)
Abstract
Background
Patients in harm-reduction treatment programs are switching from intravenous to other routes of methamphetamine (INN, metamfetamine) administration to avoid risks associated with needle use. Relatively little has been reported about the bioavailability of methamphetamine when smoked or used intranasally.
Methods
Eight experienced methamphetamine users were administered smoked or intranasal methamphetamine concurrently with an intravenous dose of deuterium-labeled methamphetamine. Plasma and urine concentrations were measured for calculation of bioavailability and other pharmacokinetic parameters by noncompartmental methods.
Results
Methamphetamine was well absorbed after smoking or intranasal administration, with bioavailabilities of 79% after intranasal administration and 67% of the estimated delivered dose or 37.4% of the absolute (pipe) dose after smoking. Maximum methamphetamine concentrations occurred at 2.7 and 2.5 hours after intranasal and smoked doses. The elimination half-life was similar for intravenous (11.4 hours), intranasal (10.7 hours), and smoked (10.7 hours) methamphetamine. Clearance (272 mL · h-1 · kg-1), steady-state volume of distribution (4.2 L/kg), and mean residence time (16 hours) of the intravenous dose were similar to previously reported values. Dextroamphetamine (INN, dexamfetamine) half-life (all routes) was 16.2 hours. Methamphetamine and dextroamphetamine renal clearances (all routes) were about 100 and 1100 mL · h-1 · kg-1, respectively.
Conclusions
Intranasal and smoked methamphetamine are well absorbed. Although intranasal or smoked routes may decrease the risk of transmission of blood-borne diseases, exposure to methamphetamine and the possibility of drug-related complications remain substantial.
From memory, the Renegade's Meth FAQ summarises dosage techniques and efficiencies
http://theposse.kicks-ass.net/renegade/wizz.html (http://theposse.kicks-ass.net/renegade/wizz.html)
Also, it is Swix's understanding that the smoke should be 'held' within to maximise diffusion-time over the gas/blood barrier in your lungs. Exhaling early simply blows your product out before it is absorbed into your blood stream.
That said, often 'early' exhaling blows out imputities that are less hydroscopic than meth (which is very hydroscopic). So based on the believed purity of your product - suck or blow the night away
P.S. Swix has had to hold back the laughs while 'expert' users prance around smoking product like a cigarette all night. Wasting all the goods to the nieve 'cool-factor' of exhaling. Swix's trusted gineau pigs don't mind as the orders keep flowing in; and they hold onto few good tokes and are right for the night...