Amsterdam bans smoking of marijuana in some public places

AMSTERDAM – A majority of the city council in Amsterdam voted in favour of introducing a city-wide ban on smoking marijuana in public in areas where young people smoking joints have been causing public nuisance.
The decision comes after a successful trial ban in the De Baarsjes district of Amsterdam.
The experimental ban led to less public nuisance, city district De Baarsjes concluded after the year-long trial.
Source: Expatica.com Jan 2007

BY MARK HENDERSON, SCIENCE CORRESPONDENT

ONE in four people carries genes that increases vulnerability to psychotic illnesses if he or she smokes cannabis as a teenager, scientists have found.
A common genetic profile that makes cannabis five times more likely to trigger schizophrenia and similar disorders has been identified, increasing pressure on the Government to reverse the drug’s reclassification from Class B to Class C.

The increased risk applies to people who inherit variants of a gene named COMT who also smoked cannabis as teenagers. About a quarter of the population have this genetic make-up, and up to 15 per cent of the group are likely to develop psychotic conditions if exposed to the drug early in life.
Neither the drug nor the gene raises the risk of psychosis by itself.
The study, led by Avshalom Caspi and Terrie Moffitt, of the Institute of Psychiatry at King’s College London, offers the best explanation yet for the way that cannabis has a devastating psychiatric impact on some users but leaves most unharmed. Scientists had suspected that genetic factors were responsible for this divide, but a gene had not been pinpointed.
The findings, to be published in Biological Psychiatry, also reinforce a growing consensus that nature and nurture are not mutually exclusive forces but combine to affect behaviour and health. The King’s team has previously identified genes that raise the risk of depression or aggression, but only in conjunction with environmental influences.
Mental health campaigners said that the results vindicated their concerns about the decision last year to downgrade cannabis to a Class C drug, which means that possession is no longer an arrestable offence.
Marjorie Wallace, chief executive of the mental health charity Sane, said that it was becoming clear that cannabis placed millions of users at risk of lasting mental illness. About fifteen million Britons have tried cannabis, and between two million and five million are regular users, according to the Home Office British Crime Survey. The research suggests that a quarter could be at risk.
The evidence will be considered by a review of the drug’s classification announced last month by the Home Secretary. It may be possible to develop a test for genetic susceptibility to cannabis. “If we were able genetically to identify the vulnerable individuals in advance, we would be able to save thousands of minds, if not lives,” Ms Wallace said.
Dr Caspi, however, rejected the idea of screening based on the COMT gene. “Such a test would be wrong more often than it is right. Cannabis has many other adverse effects, especially on developing teenagers, on respiratory health and possibly on cognitive function. Effects may be pronounced among a genetically vulnerable group but that doesn’t mean we should encourage others not genetically vulnerable to use cannabis.”
The King’s team tracked 803 men and women born in Dunedin, New Zealand, in 1972 and 1973, who were enrolled at birth in a research project. Each was interviewed at 13, 15 and 18 about cannabis use, tested to determine which type of COMT genes they had inherited, and followed up at 26 for signs of mental illness.
COMT was chosen as it is known to play a part in the production of dopamine, a brain-signalling chemical that is abnormal in schizophrenia. It comes in two variants, known as valine or methionine, and every person has two copies, one from each parent.
Among people with two methionine variants, the rate of psychotic illness was 3 per cent, the background rate for the general population, regardless of whether they had used cannabis as teenagers.
Among those with two valine variants the rate was 3 per cent for non-users but 15 per cent for those who had smoked cannabis in their teens.
Dr Caspi said research had shown that the valine gene variant and cannabis affect the brain’s dopamine system in similar fashion, suggesting that they deliver a “double dose” that can be damaging. The work needs to be replicated by others to confirm the findings, Dr Caspi said. It also is possible that the gene involved is not COMT but a neighbour.
THE DRUG OF CHOICE FOR MILLIONS
• Cannabis was reclassified from a Class B to a Class C drug in January 2004. Possession remains illegal, but is not an arrestable offence. The Home Secretary has asked for a review by November
• The Home Office estimates that fifteen million people have tried cannabis, two million to five million are regular users and reclassification has saved 199,000 hours’ police work
• Liberalisation campaigners argue that millions smoke the drug with fewer ill-effects than others suffer from alcohol or tobacco
• A recent study at Maastricht University found that cannabis doubles the risk of schizophrenia, hallucinations and paranoia among a genetically susceptible group

Source: www.timesonline.co.uk 14 April 2005

The State Government figures show that out of 4619 drivers pulled over, one in 73 tested positive to either cannabis or methamphetamines. This compared to an average of one in 250 drivers testing positive for alcohol. The results surprised police.

The results come just two days after research by the National Drug and Alcohol Research Centre showed 57 per cent of clubbers admitted driving under the influence of alcohol and 52 per cent under the influence of cannabis. The VicRoads-commissioned study reported that just under half of those surveyed admitted driving soon after taking other drugs.

43% said they had taken ecstasy and 42 % speed.

Source: Minister for Police & Emergency Services. Victoria. Australia. April 15 2005

Half of all U.S. children live in a house where a parent or other adult uses tobacco, drinks heavily or uses illegal drugs, according to a report released on Tuesday.
These adults are three times more likely to abuse their children and four times more likely to neglect them than parents who do not abuse alcohol or drugs or use tobacco, said the report from Columbia University’s National Center on Addiction and Substance Abuse.
“Children of alcohol and drug abusers are at increased risk of accidents, injuries and academic failure. Such children are more likely to suffer conduct disorders, depression or anxiety, conditions that increase the risk children will smoke, drink and use drugs,” the center said in a statement.
The report is an analysis of the center’s own research as well as dozens of reports from groups ranging from Alcoholics Anonymous, U.S. government surveys on families and health behavior and the Children’s Defense Fund, a nonprofit social welfare organization. It found that 35.6 million U.S. children, about half of all children in the country, live in a home where a parent or other adult uses tobacco, drinks heavily or uses illicit drugs.
More than 37 percent of U.S. children live with an adult who uses tobacco, nearly 24 percent live with a binge or heavy drinker and 12.7 percent live in a household where a parent or other adult uses illicit drugs, the report found.
Several studies show that children exposed to household cigarette smoke have a higher risk of sudden infant death syndrome, asthma and ear infections. They are more likely to have their tonsils or adenoids surgically removed and recent studies show they have a bigger risk of cancer and heart disease.
“If substance abusing parents are not concerned about what drugs, alcohol and tobacco are doing to themselves, they should be concerned about the ill effects they have on their children,” center Chairman Joseph Califano said.
“Children of substance abusing parents are much likelier to become substance abusers themselves,” he added.
“A child who gets through age 21 without smoking, using illegal drugs or abusing alcohol is virtually certain never to do so.”

Source: WASHINGTON (Reuters) Mar 29, 2005

[Correspondence]
Tashkin, Donald P.; Roth, Michael D.; Dubinett, Steven M.
UCLA School of Medicine; Los Angeles, CA 90095-1690

———————————————-

To the Editor: You point to largely experiential evidence of the medicinal
benefits of marijuana and the apparent absence of serious short-term toxicity.
However, a note of caution is warranted. Although it is true that smoking
marijuana carries no immediate risk of death, there may be serious adverse
effects in the very patients for whom medicinal marijuana is most commonly
considered (i.e., those whose immune defenses are already compromised by AIDS or
cancer plus chemotherapy). For example, in patients with AIDS, marijuana use has
been associated with the development of both fungal and bacterial pneumonias.
[1,2] Moreover, among HIV-positive persons, marijuana use has been shown to be a
risk factor for rapid progression from HIV infection to AIDS and the acquisition
of opportunistic infections or Kaposi’s sarcoma, or both. [3]

Cellular studies and studies in animals lend support to these potential health
consequences of marijuana. For example, delta-9-tetrahydrocannabinol has been
shown to have immunosuppressive effects on macrophages, natural killer cells,
and T cells, as well as on the response of mice to opportunistic infection. [4]
In our own studies, [5] (and unpublished data) we recovered alveolar macrophages
from the lungs of habitual marijuana smokers and found a significant reduction
in their ability to kill fungi, bacteria, and tumor cells, as well as a
deficiency in their ability to produce protective inflammatory cytokines, such
as tumor necrosis factor (alpha).

Donald P. Tashkin, M.D.

Michael D. Roth, M.D.

Steven M. Dubinett, M.D.

UCLA School of Medicine; Los Angeles, CA 90095-1690

REFERENCES

1. Denning DW, Follansbee SE, Scolaro M, Norris S, Edelstein H, Stevens DA.
Pulmonary aspergillosis in the acquired immunodeficiency syndrome. N Engl J Med
1991;324:654-62. Bibliographic Links

2. Caiaffa WT, Vlahov D, Graham NM, et al. Drug smoking, Pneumocystis carinii
pneumonia, and immunosuppression increase risk of bacterial pneumonia in human
immunodeficiency virus-seropositive injection drug users. Am J Respir Crit Care
Med 1994;150:1493-8. Bibliographic Links

3. Tindall B, Cooper DA, Donovan B, et al. The Sydney AIDS Project: development
of acquired immunodeficiency syndrome in a group of HIV seropositive homosexual
men. Aust N Z J Med 1988;18:8-15. Bibliographic Links

4. Newton CA, Klein TW, Friedman H. Secondary immunity to Legionella pneumophilia
and Th1 activity are suppressed by delta-9-tetrahydrocannabinol. Inject Infect
Immun 1994;62:4015-20.

5. Sherman MP, Campbell LA, Gong H Jr, Roth MD, Tashkin DP. Antimicrobial and
respiratory burst characteristics of pulmonary alveolar macrophages recovered
from smokers of marijuana alone, smokers of tobacco alone, smokers of marijuana
and tobacco, and nonsmokers. Am Rev Respir Dis 1991;144:1351-6. Bibliographic
Links Accession Number: 00006024-199704170-00025

Results of a new survey into cannabis use showed that 1 in 3, 15 year olds has now smoked cannabis. 18% of pupils aged 11 to 18 had taken drugs in the previous 12 months. 13% had tried cannabis in the previous year, by the age of 15, that had risen to 31%. 28% of pupils sold they had been offered cannabis. Harder drugs like cocaine ecstasy and amphetamines had been touted to 1 in 5 schoolchildren. A Dept of Health spokesman said that the no. of pupils taking drugs had decreased slightly from 20% in 2001 to 1870 in 2002. This is all in a survey of 10000 pupils by the National Centre for Social Research and The National Centre for Educational Research.

Source: Survey of 10,000 pupils by National centre for Social Research & National centre for Educational Research. Reported in daily Mail 29 March 2003

Adolescents’ use of marijuana may increase the risk of heroin addiction later in life, a new study suggests. Researchers say the work adds to “overwhelming” evidence that people under 21 should not use marijuana because of the risk of damaging the developing brain.
The idea that smoking cannabis increases the user’s chance of going on to take harder drugs such as heroin is highly contentious. Some dub cannabis a “gateway” drug, arguing that peer pressure and exposure to drug dealers will tempt users to escalate their drug use. Others insist that smoking cannabis is unrelated to further drug use.
Now research in rats suggests that using marijuana reduces future sensitivity to opioids, which makes people more vulnerable to heroin addiction later in life. It does so by altering the brain chemistry of marijuana users, say the researchers.
“Adolescents in particular should never take cannabis – it’s far too risky because the brain areas essential for behaviour and cognitive functioning are still developing and are very sensitive to drug exposure,” says Jasmin Hurd, who led the study at the Karolinska Institute in Sweden.
But Hurd acknowledges that most people who use cannabis begin in their teens. A recent survey reported that as many as 20% of 16-year-olds in the US and Europe had illegally used cannabis in the previous month.

“Teenage” rats

In order to explore how the adolescent use of cannabis affects later drug use, Hurd and colleagues set up an experiment in rats aimed to mirror human use as closely as possible.
In the first part of the trial, six “teenage” rats were given a small dose of THC – the active chemical in cannabis – every three days between the ages of 28 and 49 days, which is the equivalent of human ages 12 to 18. The amount of THC given was roughly equivalent to a human smoking one joint every three days, Hurd explains. A control group of six rats did not receive THC.
One week after the first part was completed, catheters were inserted in all 12 of the adult rats and they were able to self-administer heroin by pushing a lever.
“At first, all the rats behaved the same and began to self-administer heroin frequently,” says Hurd. “But after a while, they stabilised their daily intake at a certain level. We saw that the ones that had been on THC as teenagers stabilised their intake at a much higher level than the others – they appeared to be less sensitive to the effects of heroin. And this continued throughout their lives.”
Hurd says reduced sensitivity to the heroin means the rats take larger doses, which has been shown to increase the risk of addiction.

Drug memory

The researchers then examined specific brain cells in the rats, including the opioid and cannabinoid receptors. They found that the rats that had been given THC during adolescence had a significantly altered opioid system in the area associated with reward and positive emotions. This is also the area linked to addiction.
“These are very specific changes and they are long-lasting, so the brain may ‘remember’ past cannabis experimentation and be vulnerable to harder drugs later in life,” Hurd says.
Neurologist Jim van Os, a cannabis expert at the University of Maastricht in the Netherlands told New Scientist the research was a welcome addition to our understanding of how cannabis affects the adolescent brain.
“The issue of cross-sensitisation of cannabis/opioid receptors has been a controversial one, but these findings show the drug’s damaging effects on the reward structures of the brain,” van Oshe says. “There is now overwhelming evidence that nobody in the brain’s developmental stage – under the age of 21 – should use cannabis.”

Source: On line edition of Neuropsychopharmacology. Reported in NewScientist.com July 2006

Even mild alcohol intoxication can seriously impair drinkers’ visual acuity, according to a study from the University of Washington.
Researchers found that test subjects who consumed just enough alcohol to reach half the legal alcohol intoxication level in the U.S. performed poorly on tests of their ability to notice an unexpected visual object when they were performing another simple task. Researchers said this was the first study to demonstrate that alcohol can cause such “inattentional blindness.”
“We rely on our ability to perceive a multitude of information when we drive (speed limit, road signs, other cars, etc.),” said study lead author Seema Clifasefi. “If even a mild dose of alcohol compromises our ability to take in some of this information, in other words, limits our attention span, then it seems likely that our driving ability may also be compromised.”
The study was published in the July 2006 issue of the journal Applied Cognitive Psychology.
Reference:
Clifasefi, S. L., Takarangi, M. K. T., Bergman, J. S. (2006) Blind drunk: the effects of alcohol on inattentional blindness. Applied Cognitive Psychology, 20(5): 697-704.

Source:Reported in Medical News Today July 7, 2006

Children from families with a history of alcohol abuse show characteristics in their brains that may make them more susceptible to becoming problem drinkers themselves, a new study reports.
Using magnetic resonance imaging, researchers from the University of Pittsburgh found potentially significant structural differences in the brains of teenagers from families with multigenerational drinking problems. The report was published in a recent issue of Biological Psychiatry.
The lead author, Dr. Shirley Y. Hill, said the study had found that the right portion of a brain area called the amygdala appeared smaller than normal in the teenagers studied. The amygdala helps control emotions, the researchers said, and appears to play an important role in addictive behavior like gambling and drug use.
The researchers looked at 34 boys and young men whose family histories were believed to put them at high risk; their average age was 17. The study found that some of the deviations in the brain occurred even if the subjects were not using alcohol. They said that fact suggested a genetic component.
The researchers said they suspected that the teenagers’ brains would eventually develop normally if they avoided alcohol. But studies have shown that children from families with long histories of drinking start using alcohol earlier.
Source: New York Times July 12 2006

Yes, despite what potheads claim. Doctors in Greece compared the mental abilities of 20 people who had smoked dope four times a week for 15 years with 20 who had used it for less than seven years, and 24 never-smokers. They were given 15 words to learn, and asked to repeat them later. The average score for the long-term smokers was 7; for the shorter-term smokers, 9; for the never-users, 12. It is the latest in many studies showing repeated ‘soft’ drug abuse damages the brain. This isn’t surprising because marijuana’s active ingredient, tetrahydro cannabinol (THC), is highly fat-soluble. As our brain is the organ with the highest concentration of fat, THC makes a beeline for it and stays there for

Source: The Guardian Saturday September 30, 2006

27 October 2006

People addicted to cocaine have an impaired ability to perceive rewards and exercise control due to disruptions in the brain’s reward and control circuits, according to a series of brain-mapping studies and neuropsychological tests conducted at the U.S. Department of Energy’s Brookhaven National Laboratory.
“Our findings provide the first evidence that the brain’s threshold for responding to monetary rewards is modified in drug-addicted people, and is directly linked to changes in the responsiveness of the prefrontal cortex, a part of the brain essential for monitoring and controlling behavior,” said Rita Goldstein, a psychologist at Brookhaven Lab. “These results also attest to the benefit of using sophisticated brain-imaging tools combined with sensitive behavioral, cognitive, and emotional probes to optimize the study of drug addiction, a psychopathology that these tools have helped to identify as a disorder of the brain.”
Goldstein will present details of these studies at a press conference on neuroscience and addiction at the Society for Neuroscience (SfN) annual meeting in Atlanta, Georgia, on Sunday, October 15, 2006, 2 to 3 p.m., and at a SfN symposium on Wednesday, October 18, 8:30 a.m.
Goldstein’s experiments were designed to test a theoretical model, called the Impaired Response Inhibition and Salience Attribution (I-RISA) model, which postulates that drug-addicted individuals disproportionately attribute salience, or value, to their drug of choice at the expense of other potentially but no-longer-rewarding stimuli – with a concomitant decrease in the ability to inhibit maladaptive drug use. In the experiments, the scientists subjected cocaine-addicted and non-drug-addicted individuals to a range of tests of behavior, cognition/thought, and emotion, while simultaneously monitoring their brain activity using functional magnetic resonance imaging (fMRI) and/or recordings of event-related potentials (ERP).
In one study, subjects were given a monetary reward for their performance on an attention task. Subjects were given one of three amounts (no money, one cent, or 45 cents) for each correct response, up to a total reward of $50 for their performance. The researchers also asked the subjects how much they valued different amounts of monetary reward, ranging from $10 to $1000.
More than half of the cocaine abusers rated $10 as equally valuable as $1000, “demonstrating a reduced subjective sensitivity to relative monetary reward,” Goldstein said.
“Such a ‘flattened’ sensitivity to gradients in reward may play a role in the inability of drug-addicted individuals to use internal cues and feedback from the environment to inhibit inappropriate behavior, and may also predispose these individuals to disadvantageous decisions – for example, trading a car for a couple of cocaine hits. Without a relative context, drug use and its intense effects – craving, anticipation, and high – could become all the more overpowering,” she said.
The behavioral data collected during fMRI further suggested that, in the cocaine abusers, there was a “disconnect” between subjective measures of motivation (how much they said they were engaged in the task) and the objective measures of motivation (how fast and accurately they performed on the task).
“These behavioral data implicate a disruption in the ability to perceive inner motivational drives in cocaine addiction,” Goldstein said.
The fMRI results also revealed that non-addicted subjects responded to the different monetary amounts in a graded fashion: the higher the potential reward, the greater the response in the prefrontal cortex. In cocaine-addicted subjects, however, this region did not demonstrate a graded pattern of response to the monetary reward offered. Furthermore, within the cocaine-addicted group, the higher the sensitivity to money in the prefrontal cortex, the higher was the motivation and the self-reported ability to control behavior.
The ERP results showed a similarly graded brain response to monetary reward in healthy control subjects, but not in cocaine-addicted individuals.
“The dysfunctional interplay between reward processing and control of behavior observed in these studies could help to explain the chronically relapsing nature of drug addiction,” Goldstein said. “Our results also suggest the need for new clinical interventions aimed at helping drug abusers manage these symptoms as part of an effective treatment strategy.”

Source: Medical Research News 18th Oct.2006

27 October 2006

Researchers have found altered neural synchronization in people who smoke cannabis, providing evidence to support the link between the use of this drug and schizophrenia.

Altered neural synchronization has previously been demonstrated in patients with schizophrenia. This led Patrick Skosnik (Indiana University, Bloomington, USA) and team to suggest that such alterations may represent a neurophysiological link between schizophrenia symptoms and the neurobehavioral effects of cannabis.

The researchers assessed neural synchronization using electroencephalograms (EEG) to measure auditory steady-state potentials, eg, auditory click trains at specific frequencies – 20, 30, and 40 Hz – in 17 cannabis users and 16 drug naïve individuals.

The cannabis users showed decreased EEG power and signal-to-noise ratio at the stimulation frequency of 20 Hz compared with non-drug users.

Skosnik and colleagues note that there was no significant difference between the two groups with regard to noise power, indicating that the altered neural synchronization in cannabis users was due to decreased signal strength of oscillating circuits and not the increased noise stemming from neural background activity.

The cannabis users also demonstrated increased schizotypal personality characteristics, as assessed on the Schizotypal Personality Questionnaire, compared with controls. However, there was no significant difference between the two groups in scores on the Wechsler Adult Intelligence Scale. This demonstrates that any alterations in neural synchrony were not associated with generalized cognitive or sensory deficits, the researchers note.

Further analysis revealed that scores on the Schizotypal Personality Questionnaire positively correlated with total years of cannabis use. In addition, schizotypy scores negatively correlated with 20 Hz power, indicating that cannabis-using individuals scoring higher in schizotypy had larger deficits in neural synchronization.

“These data provide evidence for neural synchronization and early-stage sensory processing deficits in cannabis use,” the team writes in the American Journal of Psychiatry.

“Given that there is tight coupling of the endocannabinoid and dopamine systems, it appears possible that genetic anomalies leading to altered dopamine activity may interact with early cannabis exposure to produce overt psychosis.”

Source: Am J Psychiatry 2006; 163: 1798–1805
©2006 Current Medicine Group Ltd

EDINBURGH: The Scottish Executive’s anti-drug abuse policy was criticized sharply yesterday following a report that the government recommended heroin-substitute methadone is 97% ineffective.

Methadone, a drug used for recovery from heroin addiction, has a success rate of no more than 3.4%, according to Professor Neil McKeganey, chief researcher for Glasgow University’s Centre for Drug Misuse Research. McKeganey has just concluded a study on the effectiveness of the £12m a year Methadone programme.

The study observed a group of 695 heroin addicts who started taking treatment in 2001 at 33 different addiction centers across Scotland. A large percentage of this group was given methadone-based care while the rest were put on rehabilitation. Their progress was recorded over interviews 33 months after they started the treatment to see if they had become drug-free over a 90-day period.

The group given only-methadone had a very poor 3.4 percent recovery rate from drug addiction; whereas the group placed in residential rehabilitation (with no methadone throughout the treatment) showed a 29% success rate.

A key difference in methadone’s success rates between Scotland and England was also pointed out. While England emphasizes on getting people off drugs entirely, Scotland’s drug policy lacks any such direction; as a result, addicts simply substitute methadone with heroin.

McKeganey’s previous research had revealed a greater inclination to commit crimes among methadone patients when compared with addicts placed on abstinence programmes. People in the latter group also showed twice the level of interest in finding a job.

While the report makes no recommendation, sharp reactions have come in from various quarters demanding the Executive at least review its drug policy if not entirely scrap methadone. Tory leader Anabel Goldie said she recommended more investment in residential rehabilitation centres.

Meanwhile an official at the Greater Glasgow NHS facility said methadone may not be suitable for everyone but many addicts do benefit from it. He also said the government was looking to offer “a wider package of support” that would include rehabilitation, education and training, to addicts.

Source: Earthtimes.org. 30.10.06

New research shows that a synthetic analogue of the active component [THC] of marijuana may reduce the inflammation and prevent the mental decline associated with Alzheimer’s disease.

“This research is not only a major step in our understanding [of] how the brain reacts to Alzheimer’s disease, but may also help open a route to novel anti-Alzheimer’s drugs,” says Raphael Mechoulam, professor emeritus of medicinal chemistry at Hebrew University in Jerusalem and discoverer of marijuana’s active component.

To show the preventive effects of cannabinoids on Alzheimer’s disease, researchers at the Cajal Institute and Complutense University in Madrid, led by Maria de Ceballos, conducted studies using human brain tissue, as well as experiments with rats.

Source:The Journal of Neuroscience February 23, 2005

The active ingredient in marijuana may stall decline from Alzheimer’s disease, research suggests. Scientists showed a synthetic version of the compound may reduce inflammation associated with Alzheimer’s and thus help to prevent mental decline. They hope the cannabinoid may be used to developed new drug therapies. The research, by Madrid’s Complutense University and the Cajal Institute, is published in the Journal of Neuroscience.

Source:http://www.biopsychology.com/index. Feb 2005

A cannabis-based drug could help people with Alzheimer’s disease by giving them the “munchies”, researchers say.

Patients with the condition often experience weight loss because they stop recognising when they are hungry. The study does not suggest they should be given cannabis to smoke – instead, they tested a synthetic version of a cannabis extract. It was found the cannabinoid led to weight and reduced agitation, another symptom of the disease. The researchers from the Meridian Institute for Aging in New Jersey looked at a drug called dronabinol which is an artificial version of delta-9 THC, the active ingredient in cannabis.

Dronabinol may reduce agitation and improve appetite in patients with Alzheimer’s disease

Dr Joshua Shua-Haim, Meridian Institute for Aging

Source: BBC report 21 Aug.2003