Marijuana drug interactions

The possibility that marijuana might interact with antiepileptic drugs is currently under discussion (23 ). Both the human evidence just cited and earlier animal work point to a positive interaction with barbiturates, but there are also earlier clinical reports suggesting that marijuana can actually precipitate epileptic seizures in certain subjects, and in such cases epileptic therapy might be rendered less effective. 

The involvement of the cerebellum in the psychoactive effects of marijuana and in changes in rCMR is consistent with the view that THC interacts with the high concentration of CB1 receptors in this brain area. Decreases in the cerebellar rCMR in habitual marijuana users may reflect the effects of chronic exposure to the drug. Functions known to be associated with the cerebellum, such as motor coordination, proprioception, and learning, are adversely affected both during acute marijuana intoxication and in habitual users. 

The dopaminergic system plays a role in the abuse liability for some, if not most, drugs. The stimulants — opiates, marijuana, nicotine, and ethanol — all interact directly or indirectly with... 

The use of cannabinoids has been studied in 62 patients with HIV-1 infection (143). Cannabinoids and HIV are of interest because there is the chance of an interaction between tetrahydrocannabinol and antiretroviral therapy. Tetrahydrocannabinol inhibits the metabolism of other drugs (144,145) and cannabinoids are broken down by the same cytochrome P-450 enzymes that metabolize HIV protease inhibitors. The subjects were randomly assigned to marijuana, dronabinol (synthetic delta-9-tet-rahydrocannabinol), or placebo, given three times a day, 1... 

Most inhalant abusers are also abusing other drugs. According to the Drug and Alcohol Services Information System Report (March 2002), out of 2,091 adolescents admitted to substance-abuse programs in 1999 reporting use of inhalants, only 569 reported inhalant abuse as their primary problem. More than half of the inhalant abusers reported use of both alcohol and marijuana. Primary inhalant abusers were 0.4% of the total reported admissions for any type of substance abuse. This makes the interactions between drugs an important area for further study. 

Pertwee RG (1992) In vivo interactions between psychotropic cannabinoids and other drugs involving central and peripheral neurochemical mediators. In Murphy L, Bartke A (eds) Marijuana/cannabinoids. Neurobiology and neurophysiology. CRC Press, Boca Raton, p 165... 

Marijuana remains one of the most widely used and abused drugs in the world. Over the past decade there have been major advanees in understanding the mechanisms whereby marijuana interacts with the brain, producing psychoactive and potentially therapeutic effects. Recent findings indicate the existence of an endocannabinoid physiological control system (EPCS) whose role is just beginning to become understood. 

Acute and chronic administration of alcohol can inhibit the biotransformation or detoxification of many drugs, such as barbiturates, meprobamate, and amphetamines by liver enzymes. The effect can occur in two opposite ways. Alcohol and cannabinoids effects are additive. Both are CNS depressants. Animal studies indicate that simultaneous administration of alcohol and tetrahydrocannabinol (THC), the psychoactive component of marijuana, increased the tolerance and physical dependence to alcohol. Human studies show that alcohol and THC combination enhanced the impairment of physical and mental performance only, and there is no evidence of any interaction between both drugs. With barbiturates. 

The components of marijuana that create both the drug s high and its medicinal effects belong to a family of chemicals called cannabi-noids. Marijuana contains more than sixty different cannabinoids, all found only in the cannabis plant. Furthermore, when marijuana is heated or burned, chemical changes occur that increase the number of cannabinoids and their derivatives. The resulting large number of chemicals interact in complex ways. This is one of the reasons marijuana is so difficult to study. 

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