Marijuana subjective effects

Wachtel SR, El Sohly MA, Ross SA, et al Comparison of the subjective effects of deltaO-tetrahydrocannabinol and marijuana in humans. Psychopharmacology... 

The average increase in rCMR after THC administration was less in marijuana users than in controls, and users had lower cerebellar metabolism than the controls at baseline [8]. Thus the cerebellum shows the greatest metabolic increase in response to acute THC and responds to chronic marijuana exposure with a decrease in baseline CMR. Habitual users but not controls responded to THC administration with increased rCMR in prefrontal cortex, orbitofrontal cortex, and basal ganglia. In contrast to the robust effects of THC on relative rCMR, changes in global CMR in response to THC were quite variable, with increases, decreases, and no changes seen in equal numbers of subjects. There was also variability in subjective effects, which were pleasurable for most subjects but either minimal or unpleasant (anxiety or paranoia) for others. 

Chait LD and Zacny JP (1992). Reinforcing and subjective effects of oral D9-THC and smoked marijuana in humans. Psychopharmacology, 107, 255-262. 

Cone EJ, Johnson RE, Moore JD, Roache JD. (1986). Acute effects of smoking marijuana on hormones, subjective effects and performance in male human subjects. Pharmacol Biochem Behav. 24(6) 1749-54. 

Compared to the 2- hour duration of the subjective effects of natural marijuana, the effects of a mixture of the eight isomers of this synthetic derivative lasted much longer - up to 30 hours. We gave some Dexedrine to the above subject to see if it would reduce or shorten his symptoms. Not surprisingly, his alertness improved but all the other effects persisted unchanged. 

Marijuana produces a distinctive behavioral syndrome that is easily distinguished from that of most other drugs. The most prominent feature is the initial period of euphoria, or high, which has been described as a sense of well-being and happiness. Euphoria is frequently followed by a period of drowsiness or sedation. Perception of time is altered, along with distortions in both hearing and vision. However, illusions and hallucinations occur infrequently. The subjective effects also include dissociation of ideas. 

The subjective effects of marijuana vary from individual to individual as a function of dose, route of administration, the experience and expectation of the subjects, and individual vulnerability to certain psychoactive substances. Motor coordination also may decrease, especially in situations requiring highly complex motor skills, such as flying an airplane and driving an automobile. 

CS438 Block, R. I., W. J. Erwin, R. Farinpour, and K. Braverman. Sedative, stimulant, and other subjective effects of marijuana relationships to smoking techniques. Pharmacol Biochem Behav 1998 59(2) 405-412. 

Lukas SE, Orozco S. Ethanol increases plasma delta(9)-tetrahydrocannabinol (THC) levels and subjective effects after marijuana smoking in human volunteers. Drug Alcohol Depend 2001 64(2) 143 9. 

Another study by Haney and her colleagues was designed to examine the effects of naltrexone in heavy marijuana users. The goals of this experiment were to examine whether naltrexone would (1) block marijuana s pharmacological effects, and (2) precipitate withdrawal in heavy marijuana users (Haney et al. 2003a). Naltrexone failed to elicit these actions however, it did increase many of the positive subjective effects of oral THC in heavy marijuana smokers. An implication of these findings is that naltrexone may be expected to increase marijuana use. 

A. Subjective effects after smoking a marijuana cigarette include euphoria, palpitations, heightened sensory awareness, and altered time perception followed after about 30 minutes by sedation. More severe intoxication may result in impaired short-term memory, depersonalization, visual hallucinations, and acute paranoid psychosis. Occasionally, even with low doses of THC, subjective effects may precipitate a panic reacticn. 

Key Words Cannabis marijuana dronabinol human smoked adverse events cardiovascular neurological cognition performance subjective effects. 

Other Substances. Driving under the influence of alcohol cases are compHcated because people sometimes consume alcohol with other substances (11—13). The most common iUicit substances taken with alcohol are marijuana and cocaine (see Table 1) (14). In combination with alcohol, some dmgs have an additive effect. When a blood or urine alcohol sample is tested for alcohol and the result is well below the legal concentration threshold yet the test results are not consistent with the arresting officers observation that the subject was stuporous, further toxicological tests for the possible presence of dmgs are indicated. 

Vachon L, Fitzerald MX, Solliday NH, Gould IA, Gaensler EA. Singledose effect of marijuana smoke bronchial dynamics and respiratory-center sensitivity in normal subjects. N Engl J Med 1973 288 985-989. 

Relatively few human imaging studies have evaluated the effects of marijuana or THC on metabolism or blood flow. Acute intravenous THC in both normal controls and habitual marijuana users led to increased an increased regional cerebral metabolic rate (CMR) in the cerebellum. This increase is positively correlated both with concentrations of THC in the plasma and with the intensity of the subjective sense of intoxication [5]. In a 1997 PET/[lsO]water study with 32 abusers [6], THC dose-depend-ently increased cerebral blood flow (CBF) in the frontal regions, insula... 

The reduction of nausea in patients taking anti-cancer drug therapy is probably the most widely researched area for cannabis therapy. A number of these studies have shown that oral administration of isolated cannabinoids produce significant improvements, particularly for those patients who have failed to respond to standard antinausea treatments during chemotherapy (see Tortorice and O Connell, 1990 for a comprehensive review). Patients and oncologists have subjectively reported that smoked marijuana is as safe (in this patient group) and effective as isolated oral cannabinoids, but more systematic research trials are required. 

Chait LD. (1990). Subjective and behavioral effects of marijuana the morning after smoking. Psychopharmacology (Berlin). 100(3) 328-33. 

Heishman SJ, Stitzer ML, Yingling JE. (1989). Effects of tetrahydrocannabinol content on marijuana smoking behavior, subjective reports, and performance. Pharmacol Biochem Behav. 34(1) 173-79. Herkenham M, Lynn AB, Johnson, MR, Melvin LS, de Costa BR, Rice KC. (1991). Characterization and localization of cannabinoid receptors in the rat brain a quantitative in vitro autoradiographic study. J Neurosci. 11 563-83. 

From a potency standpoint, the results were less than exciting. At low doses, performance scores did decline slightly and some subjects reported mild symptoms suggestive of marijuana effects. However, a substantial alteration in both cognitive performance and mood occurred only in one of the two individuals who received the highest dose (60 mcg/kg). This volunteer clearly showed a drop in performance scores, and developed clear-cut signs and symptoms of a marijuana high. 

Tolerance develops to many of A -THC s effects in heavy marijuana users. Although chronic cannabis use does not result in severe withdrawal symptoms, numerous case reports attest to development of dependence in subjects taking high doses of THC for several weeks. The most prominent symptoms were irritability and restlessness others included insomnia, anorexia, increased sweating, and mild nausea. Cessation of mild or moderate use of marijuana, however, does not produce a withdrawal syndrome. 

Donovan et al. (1996, 1997) completed an open study evaluating the use of valproic acid (Depakote) in adolescent outpatients with marijuana abuse or dependence and explosive mood disorder (mood symptoms were not classified using the DSM FV Diagnostic System). Eight subjects were prescribed 1000 mg of valproic acid (Depakote) for 5 weeks, in addition to regular therapy sessions, but did not receive any other psychotropic medications. All subjects showed a significant improvement in their marijuana use (p <0.007) and their affective symptoms (p < 0.001), although both outcomes were measured only by self-report. The most common adverse events were nausea and sedation. No subjects discontinued because of these side effects, nor were there any reported interactions between the valproic acid (Depakote) and substances of abuse. 

Pope et al.225 found neuropsychological impairment during the first week of abstinence, but by day 28, there were no differences between daily smokers and control subjects. Both studies found that daily smokers evidenced greater impairment than less frequent smokers, which is consistent with the dose-related effect noted above for acute marijuana studies. 

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