Marijuana pharmacology

Cannabinoids were used in medicine in the form of their crude extracts many centuries ago. Lately the use of cannabis for so-called recreational purposes has become a national vice of substantial proportions. Several attempts have been made to focus the potentially useful pharmacological properties of marijuana into drug molecules with no abuse potential. 

There are over 400 constituent compounds in marijuana. More than 60 of these are pharmacologically active cannabinoids, of which 4 are the most important. The most psychoactive is delta-9-tetrahydrocannabinol (A-9-THC). The other three important natural cannabinoids are A-8-THC, cannabinol and cannabidiol (Kumar et al., 2001). In addition, some of the metabolites of THC, such as 11-hydroxy-A-9-THC, are also psychoactive. As a consequence and contrary to many other drugs, the metabolism of THC in the liver does not decrease intoxication, rather it prolongs it. 

Heishman SJ, Arasteh K and Stitzer ML (1997). Comparative effects of alcohol and marijuana on mood, memory, and performance. Pharmacology, Biochemistry and Behaviour, 58, 93-101. 

Marijuana (reefer, pot, grass, weed) is the most commonly used illicit drug. The principal psychoactive component is A9-tetrahydrocannabinol (THC). Hashish, the dried resin of the top of the plant, is more potent than the plant itself. Pharmacologic effects begin immediately and last 1 to 3 hours. 

As Fred expressed in a memo, if the labs had any pride in their work, they would not only admit doing such research, but would point out the relative void in pharmacological knowledge about marijuana and let the world know that we were perfectly positioned to help fill it. We had sophisticated equipment, an excellent testing environment and a ready supply of volunteers. But Fred s arguments came to naught. 

There was an unmistakable discomfort shared by the gentlemen from Washington. After a bit of discussion 1 volunteered the statement, "Of course, with three chiral centers, there will be eight distinct optical isomers possible, all of different pharmacology, and some may not resemble marijuana at all in action." The meeting broke up shortly thereafter. A lot of things just couldn t be talked about. 

Pharmacology Dronabinol is the principal psychoactive substance present in Cannabis sativa L (marijuana). The mechanism of action is unknown. 

The most consistent pharmacological effect produced by marijuana is tachycardia, which is closely associated with the blood levels of A -THC. There is relatively little effect on blood pressure unless large quantities of marijuana are smoked, in which case there can be marked orthostatic hypotension. Cannabinoids are also vasodUatory, which results in the characteristic conjunctival reddening following marijuana smoking. They also reduce intraocular pressure and are capable of producing bronchodilation. 

Little is known about the pharmacology of DMHP and DMHP acetate, but the reference compound, THC, has been extensively described both in humans and in animals. Many reviews and symposia have discussed marijuana and the cannabinoids.6>10>l9 26,39 National Insti-... 

This book will focus on forensic pharmacology and drugs of abuse. Drugs of abuse, such as cocaine, heroin, marijuana, PCP, benzodiazepines, and methamphetamine, are often involved in criminal and civil matters concerning personal injury, motor vehicle accidents, drug overdose, and murder, and thus, are discussed to illustrate forensic pharmacology issues and investigations. 

Gardner, Eliot L., and Joyce H. Lowinson. 1991. "Marijuana s Interaction with Brain Reward Systems Update 1991." Pharmacology Biochemistry and Behavior 40 571-80. 

O Leary, D.S. et al., Effects of smoking marijuana on brain perfusion and cognition, Neumpsycho-pharmacology, 26, 802, 2002. 

The time spent reviewing the pharmacology of marijuana, nicotine and alcohol was just right. ... 

Practitioners throughout the world have used marijuana. The most sophisticated pharmacological studies have shown for more than two decades that the active ingredients of marijuana are efficacious in the following conditions ... 

---