Marijuana absorption

Cannabis may be smoked like a cigarette (a joint ), or in a water pipe (a bong ) or a regular pipe (a bowl ). Smokers typically inhale deeply and hold their breath to maximize the amount of THC absorption by the lungs. Marijuana can also be eaten and is sometimes prepared in brownies or other baked goods. 

Because THC-acid and much of the delta-6-trans isomer are converted by heat or combustion into the delta-1 form, the effects of smoking and eating are quite different. (Absorption from the lungs is said to be about three times more effective than when marijuana passes through the stomach.)... 

Cannabis in the New World Committee Reports on Marijuana Epidemiology Methods of Use Active Ingredients Pharmacokinetics Absorption... 

We begin this chapter with a historical overview of marijuana and its use through the centuries. This is followed by a section on the epidemiology of current marijuana use. Next we provide information on absorption, distribution, metabolism, and excretion mechanisms of action and tolerance and dependence. Follow ing this is an overview of the medical and p-sychotherapeutic uses of marijuana. The chapter s final sections concern the physical, psychological, and social/environmental effects of marijuana. 

The absorption of THC depends primarily on the mode of consumption. The most rapid and efficient absorption of marijuana occurs through smoking. Inhalation results in absorption directly through the lungs, and the onset of the THC action begins within minutes. Assessments of blood plasma reveal that peak concentrations occur 30-60 minutes later. The drug effects can be experienced for two to four hours. 

The therapeutic uses of marijuana today arc much more circumscribed. For the most part synthetic products (such as dronabinol [trade name Marinol] and nabilonc [Cesamet]) that chemically resemble the cannabinoids have been used in current treatment efforts because they provide the active elements of THC in a more stable manner (see Joy ct al., 1999 Sussman, Stacy, Dent, Simon, Johnson, 1996). Synthetics also can provide better solubility. Unfortunately, a downside to the synthetics is the absence of the rapid effect experienced when marijuana is smoked. When synthetic THC is taken orally, it is broken down prior to entering the bloodstream and absorption thus is delayed. A recent development with promise is a cannabis oral spray (trade name Sativex), which has been approved in Canada for use as a painkiller for sufferers of multiple sclerosis. 

The balance between medicinal use of a drug and the abuse potential is a delicate balance. One of the main points brought by the medicinal marijuana proponents is the fact that the currently available soft gelatin capsule formulation is very expensive and lacks consistency in its effects. The latter point could be explained based on the fact that oral THC has erratic absorption from the gastrointestinal tract, is subject to the first-pass effect resulting in heavy metabolism with production of high levels of 11-OH-THC, and undesirable side effects. 

Joern WA. Surface absorption of the urinary marijuana carboxy metabolite The problem and a partial solution. J Anal Toxicol 1992 16 401 (Letter). 

CAS 4685-14-7. [CH3(C5H4N)2CH ] 2CH3S04. Properties Yellow solid. Soluble in water. Hazard Highly toxic by ingestion, inhalation, and skin absorption use is restricted. TLV 0.1 mg/m3. Use A widely used non-selective herbicide that kills all green plant tissue it contacts, especially grasses and weeds. Has been used to kill marijuana crops. 

Keywords Cannabinoids Pharmacokinetics Tetrahydrocannabinol Cannabidiol Absorption Distribution Metabolism Excretion Interpretation Oral fluid Sweat Hair Plasma Urine Alternate matrix Marijuana... 

Harvey DJ (2001) Absorption, distribution, and biotransformation of the cannabinoids. In N ias GG, Sutin KM, Harvey DJ, AgureU S (eds) Marijuana and medicine. Humana Press, Totowa, pp 91-103... 

Huestis MA, Henningfield JE, Cone EJ (1992b) Blood cannabinoids. 1. Absorption of THC and formation of 11-OH-THC and THCCOOH during and after smoking marijuana. J Anal Toxicol 16 276-282... 

Huestis MA, Sampson AH, Holicky BJ, Henningfield JE, Cone EJ (1992d) Characterization of the absorption phase of marijuana smoking. Clin Pharmacol Ther 52 31-41... 

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