Kindle Notes & Highlights
Read between
May 13 - July 14, 2019
Marijuana intoxication can heighten anxiety, but this brief reaction should not be confused with an anxiety disorder.
These findings suggest marijuana probably does not cause schizophrenia. Although the drug does not cause the disorder, marijuana may exacerbate psychotic symptoms in schizophrenics.
Cannabis may not cause psychopathy, but psychopaths often smoke cannabis.
Careful research on humans shows no structural changes associated with chronic cannabis exposure in adulthood.
In contrast to all of these studies that found no structural changes in adults, adolescent users of marijuana may alter the development of their brains.
Although advanced techniques in brain imaging reveal that those who start cannabis use in adulthood show no marijuana-induced changes in brain structure, chronic cannabis consumption might alter brain function.
A different study, which avoided any problem with benzodiazepines, revealed that experienced users had lower CBF than controls (Mathew & Wilson, 1992).
who smoked at least weekly for over 5 years (Volkow et al., 1996). Although not all studies of this type reveal differences, the sum of these data suggest that frequent, chronic consumption of cannabis has a detectable impact on the functioning of the cerebellum, lowering blood flow and metabolism in the area.
Chronic exposure to large doses of cannabis clearly alters the EEG in animals (Solowij, 1998).
People who smoke cannabis but not cigarettes rarely experience lung problems.
Visual inspections of the lungs revealed that people who smoked 5 joints a week for 2 years had more redness, swelling, and mucous.
Thus, even without creating emphysema, marijuana can alter the bronchial tract.
These data are comparable to early studies of tobacco and cancer and suggest that cannabis smoke is capable of damaging the bronchial system in ways that may lead to tumors.
For example, children exposed to marijuana prenatally showed problems with a sustained attention task when they reached age 6 (Fried, Watkinson, & Gray, 1992). Another commendable longitudinal study followed over 600 mothers through pregnancy until their children reached age 10 (Goldschmidt, Day, & Richardson, 2000).
Many people employ cannabis in the battle against AIDS-related wasting and the anorexia associated with cancer chemotherapy.
Marijuana does not appear to have a toxic dose.
These results confirm that marijuana is neither completely harmless nor tragically toxic.
Compared to other drugs that are currently legal, its impact on health is minimal.
Cannabis seems to have fewer negative health effects than legal drugs, like alcohol, caffeine, or tobacco, and kills far fewer people.
Medicinal uses for cannabis date back to 2737 B.C., when the Chinese emperor and pharmacologist Shen Neng prescribed the drug for gout, malaria, beriberi, rheumatism, and memory problems.
By 1942, against the recommendation of the American Medical Association, the U.S. Pharmacopoeia removed marijuana from its list of medications.
In 1970, the Comprehensive Drug Abuse Prevention and Control Act separated substances based on perceptions of their medical utility and liability for abuse. The act placed marijuana in Schedule I with heroin, mescaline, and LSD, making it unavailable for medical use.
Long-term health effects appear in chapter 7, but smoked marijuana for brief interventions or as a treatment for the terminally ill has no more negative side effects than many other popular drugs.
Controlled studies reveal that cannabinoids can decrease pressure inside the eye for glaucoma patients, alleviate pain, reduce vomiting, enhance appetite, promote weight gain, and minimize spasticity and involuntary movement. Other work suggests additional therapeutic effects for asthma, insomnia, and anxiety. Yet only a few studies have compared cannabinoids to established treatments for these problems.
These include seizures, tumors, insomnia, menstrual cramps, premenstrual syndrome, Crohn’s disease, tinnitus, schizophrenia, adult attention deficit disorder, uncontrollable violent episodes, post-traumatic stress disorder, and, surprisingly, drug addiction.
After a decade of basic research, investigators in the West Indies developed Canasol, a cannabis derivative administered as eye drops that can lower intraocular pressure. Unlike the first THC eye drops, Canasol can decrease intraocular pressures up to 50% within 15 minutes.
These data support marijuana’s analgesic effects, using a more reliable pain measure.
No one has developed lung cancer from smoking marijuana for a few months.
Most studies of chemotherapy and nausea reveal that THC can enhance appetites in cancer patients. People with HIV and AIDS have also benefited from oral cannabinoids, showing weight gain (or at least slowed weight loss), as well as improved appetite and mood.
Unfortunately, cannabis smoke does impair macrophages, the primary immune cells of the lungs.
In the first study of therapeutic cannabis in this population, researchers in a spinal cord clinic reported that 5 of 8 men who used marijuana felt it decreased their spasticity (Dunn & Davis, 1974).
By the 1970s, clinical lore praised marijuana’s potential therapeutic effects for alleviating spasms.
Overall, cannabinoid treatments for involuntary movement show more promise for Tourette’s and dystonia than Huntington’s chorea and Parkinson’s.
Seizures caused by epilepsy may decrease in response to cannabinoids, particularly cannabidiol (Petro, 1997b).
A few small-scale human experiments, animal investigations, and case studies suggest that cannabinoids may help treat insomnia and anxiety, decrease asthma symptoms, shrink tumors, kill microbes, and alleviate arthritis pain.
A small sample of insomniacs fell asleep more quickly after taking THC, but side effects at the highest dose (30 mg) were excessive (Cousens & DiMascio, 1973).
In addition to its efficacy as a sleep aid, cannabidiol may work as an anxiolytic.
Animal research beginning in the 1970s revealed that cannabinoids could shrink tumors (Harris, Munson, & Carchman, 1976).
A study of rats suggests that THC’s analgesic effects can apply in arthritis, alleviating pain and stiffness (Smith, Fujimori, Lowe, & Welch, 1998). Other animal studies show that cannabinoids may fight inflammation, bacteria, microbes, and fungi (Kabilek et al., 1960; Turner & ElSohly, 1981).
These include beneficial outcomes for treating menstrual cramps, premenstrual syndrome, Crohn’s disease, tinnitus, schizophrenia, adult attention deficit disorder, uncontrollable violent episodes, post-traumatic stress disorder, depression, and bipolar disorder. At least one surprising case shows cannabis has helped end addiction to other drugs.
Treatments should begin with THC in pill form, obtained through a physician’s prescription.
In general, cannabinoids show promise as medicine but require a great deal of additional study.
Despite data to the contrary, stereotypes suggest that regular users of cannabis, particularly adolescents, transform into apathetic slugs uninterested in school, work, or any productive activity (Nahas, 1990).
Despite evidence to the contrary, concern about marijuana’s influence on motivation continues today (NIDA, 1998).
Chronic cannabis users rarely report the drastic financial, social, and occupational difficulties typical of addiction to alcohol, opiates, or cocaine.
Making fewer chairs might reflect lower motivation, but it more likely offers further evidence that intoxication impairs performance.
The men showed statistically comparable total responses, total correct responses, errors, and time worked throughout the 94-day period (Cohen, 1976). These data offer no support for amotivational syndrome.
The responses returned to normal within 3 months of abstinence from cannabis, when all groups performed equally well (Slikker, Paule, Ali, Scallet, & Bailey, 1992).
This study of primates shows decreased performance on a difficult exercise after a year of marijuana use, but only in those who had practiced the task during their exposure to cannabis.
This study and some of the human research certainly confirms that intoxication can impair performance on some tasks in some conditions.
