‘Cannabis psychosis’ – an early warning!

Last Sunday’s blog created an interesting degree of feedback, some of which was sent via the UKCIA contact form rather than as comments to the actual blog.

One comment posted to the blog needs addressing: Steve  Rolles wrote

I think the problem has not been no evidence for mental health risks – there clearly is a considerable amount, enough to assume that the ambiguity on individual studies, should not be used to conclude there is no link.

That wasn’t the intention. Last weeks blog was purely aimed at highlighting the way the mental health issue was used to discredit the tentative steps toward law reform the original reclassification had been. But not only did it discredit the law reform, it may have possibly served to prevent a greater understanding of what is actually happening and maybe even prevent an important development in both societies approach to drug use and the understanding of mental health problems.

For those interested, and thanks to feedback from last week’s blog, the research carried out in Denmark (Familial Predisposition for Psychiatric Disorder)  mentioned in that blog is here. It makes some interesting conclusions:

Altogether, these findings, in addition to those of previous studies, indicate that cannabis-induced psychosis may not be a valid diagnosis but an early marker of schizophrenia. Replication of the results would further strengthen this assertion.


However, the results clearly show that cannabis-induced psychoses do not occur randomly. Rather, the degree of hereditary predisposition in individuals who receive treatment of cannabis- induced psychosis closely mirrors that in those who develop schizophrenia with no history of cannabis induced psychosis. The results agree with those of other studies that show that cannabis predominantly causes psychotic symptoms in those persons who are predisposed to develop psychosis or show signs of psychosis in the absence of cannabis use


Psychotic symptoms after cannabis use should be taken extremely seriously. It is recommended that individuals with a cannabis-induced psychosis according to ICD-10 criteria be treated as though the condition is a first sign of schizophrenia, regardless of predisposition to a psychiatric disorder. Psychotic symptoms after cannabis use that are short-lived or do not require treatment should be the focus of future prospective studies because such symptoms could be important indicators of risk of schizophrenia and other severe psychiatric disorders. In addition, future studies should compare the clinical course after cannabis-induced psychoses with that of other psychotic disorders.

This seems pretty clearly to imply a bad – ie psychotic – reaction to cannabis is an early warning of a pre-existing developing mental illness, or at least the person concerned being at risk of developing such an illness, so-called “cannabis psychosis” is a taste of the real thing.  There are, of course, few such indicators available to identify people at risk of such an illness. We need to make it as easy as possible to identify such people and a bad reaction to cannabis, spotted early, would do just that. Prohibition will act to prevent this early identification.

Now of course, getting someone stoned to see if they get a psychotic attack is a bit of a hard way to check for an emerging illness, so is there anything else we could be looking for, short of a seriously bad reaction like this? Well, the answer to that is “yes”, and it’s a bit obvious.

Looking back on the RETHINK cannabis and mental health campaign which ran from 2004, they related several stories of young people who had been heavy cannabis users who went on to develop severe mental illness. The key words there are “young people” and “heavy users”. Every example of a young person claimed to have been harmed by cannabis UKCIA heard of had been a heavy user, there is something of an elephant in the room that no-one noticed and actually it could be a small herd of elephants.

Now there are many reasons to want to keep kids – children and young teenagers – away from drugs and the lack of control over the illegal trade is just one of destructive effects of prohibition.

Beyond the issue of child protection and the need for age limits on sales however, the type or nature of the cannabis use these people seem to have shown is not typical of most stoners. Now it’s not unknown for anyone who dabbles in cannabis to have a “session” from time to time, which means a fair amount getting consumed and everyone getting very stoned, just as normal, non-problematic drinkers get sloshed from time to time. It’s also reasonably normal for there to be a “honeymoon” period where getting stoned is nothing but fun and gets done a bit too much, but this doesn’t last long, most people have lives and their cannabis use takes its place in the general run of things.

But for some people – the problem users – it doesn’t work like that. For a few cannabis use comes to dominate their lives. They smoke as often as possible every day, even to the determent of other aspects of their daily routine.  This abnormal behaviour is possibly the real early indication of a problem and is thus the thing we should be looking out for.

Now of course the big problem is we don’t have a “norm” for social cannabis use, despite it having been pretty normal for something like half a century in this country. Prohibition has ensured that the social norms which would have developed around cannabis use simply haven’t been allowed to do so. Worse, the stereotypical image of a stoner promoted by the drug warriors has always been the unwashed waster, an image far removed from the truth for the vast majority, but perhaps not the minority we need to identify.

In truth we have a minority of people who are at risk of a serious illness and who need identifying and their reaction to cannabis might do just that. They deserve the protection of the law rather than to be treated as the enemy, but perhaps most importantly they need their mates to be aware of the signs. It’s only by the development of social norms that ordinary people can be expected to spot the unusual. During the RETHINK campaign one of the most outspoken campaigners spoke of how his son’s friends did notice his unusual behaviour, but they didn’t know what to do about it. This is little short of tragic.

Back in 2004 UKCIA attended the first “Cannabis and Mental Health” conference in London, organised by Robin Murray and other prominent psychiatrists. We were invited to provide a paper which was included in the delegates pack, which can be seen here

We wrote back then of the need to make cannabis users aware of the signs to look out for and suggested something like this as information to provide to cannabis users:

What to watch out for

If you know someone – especially someone young (in their teens or younger) who’s using a lot of cannabis it might be an idea to check out what’s going on.

Although it is not proven that cannabis can actually cause mental health problems it is true that sufferers tend to use a lot of it and when they do it seems to make their condition worse.

We’re not morbid!

It could be that heavy cannabis use is an early indication of a developing problem, something scientists call a “premorbid” indication; nothing to do with being sad, “premorbid” means it could be an indication of developing mental health problems, a sign that something is wrong.

Prolonged heavy use isn’t the norm even for a rebellious youth, it should always be a cause for concern. So if a young person is using a lot of cannabis, don’t ignore it, you might be seeing a warning sign.

Whether or not cannabis causes any illness, or even just makes it worse, the simple advice is that it’s best say people under 18 shouldn’t get stoned.

This latest research would seem to support this line of reasoning. Returning cannabis to class B and resorting to ever more prohibition isn’t going to help in the slightest though, indeed it will only cause more harm.

Finally, back to the herd of elephants in the room. The lack of social norms is a pretty big one, but it’s not alone.

Last week we reported a Guardian story that claims the decrease in tobacco use by young people is in itself leading to a decrease in cannabis use. This would seem to be addressing the problem  simply by virtue of the fact that less people are using cannabis, sadly in itself its not likely to.

Tobacco use is falling in society generally, but amongst people with severe mental illness it’s still very common, indeed they tend to be heavy smokers. Strange to note but there has never been a “fags madness” campaign despite the correlation of tobacco use and severe mental illness. However, as it’s still the norm for cannabis to be smoked with tobacco then people who are likely to be heavy tobacco smokers anyway are more likely to smoke a lot of cannabis as a result.

As with all problems, if we can face one at a time they are easier to deal with. Sadly there is a deeply entwined relationship between cannabis and tobacco  in the UK. This isn’t a “natural” relationship and in many places around the globe the two are thought of as quite distinct. A safer use campaign designed to separate the two would surely reduce the problems further. The government, of course, will have non of it.

3 thoughts on “‘Cannabis psychosis’ – an early warning!

  1. The last chapter about tobacco struck a familiar chord. I’m a Finn in his late 20s who has witnessed first hand the dramatic change we’ve experienced in local cannabis culture during the past 10 years.

    In the 1990s, practically the only cannabis around was imported hash. It was always mixed with tobacco before it was smoked in joints or pipes. This happened both because hash is difficult to smoke “raw” and because cigarettes were already a part of the Finnish toolkit of intoxication. Also, this is the kind of culture one would expect to develop where cannabis is scarce and expensive.

    During this millennium personal cultivation of cannabis has exploded. One of the main reasons for it has been the general motivation amongst users to become self-sufficient and sever ties to organized crime and the variable-quality product associated with it.

    Active Finnish cannabis users have traditionally been a peace-loving lot who have never enjoyed mingling with thugs. And once these people started constructing a new kind of cannabis culture to replace the old, hash-centered one, they became increasingly troubled by many of its external symbols, including tobacco use.

    Tobacco is still widely used among Finnish cannabis smokers. It is, after all, a highly addictive substance. But more and more people are toking up on nothing but parts of the cannabis plant. And lately there has been a marked increase in the popularity of vaporizers and oral ingestion methods as well.

    Seizures of imported hash have roughly halved and home-grown cannabis seizures have more than doubled since 2001. The grassroots cannabis culture seems to have succeeded in what the police couldn’t do with all their efforts. It has taken a lion’s share directly out of the smugglers’ profits.

    But the prohibitionists insist that it’s the police who have managed to cut smuggling, and that they should now go after home growers. We’re currently seeing an effort to import the British skunk hysteria to Finland as well.

    While the Finnish cannabis culture is cutting down on tobacco and other nasties, the powers that be seem to want the old days to return. Too bad they don’t seem to know what those old days were actually about.

  2. This article ended with the point that “government will have none of” an effort to address the disastrous public health issue of children in the UK being misled into combining tobacco with cannabis. Extremely important to follow government leaders’ tracks– such as Clegg’s comment that the stress of government duty makes him crave more $igarettes; politicians’ relations with lobbyists (lawbuyists) from Big 2WackGo; the influence on government of the huge $igarette tax BRIBE system (in some countries, such as Pakistan, reportedly as high as 10% of total government income)– and what measures the Industry is able to demand against its enemy Cannabis.

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