“Psychosis is associated with more frequent and longer use of cannabis.” – Di Forti et al
After alcohol, marijuana is the most used psychotropic drug in America. In 2018, more than 11.8 million young adults reported marijuana use in the past year. Marijuana (also known as cannabis, weed, pot, dope, or grass) is the most widely used illegal drug in the UK; however, in the United States, we have seen a widespread shift towards the legalization of this drug. So far, 15 U.S. states and Washington D.C. have legalized marijuana for adult recreational use, and 36 states permit medical use of the drug.
Legalizing marijuana for medical and recreational use has bolstered an already widespread opinion that cannabis is a “soft drug,” that its effects are benign, and that it is almost a rite of passage for the young that is no more dangerous than taking your first sip of wine.
The National Institute on Drug Abuse reports that there is a significant gender discrepancy in America, as cannabis use is far more prevalent among young males than young females. The effects also vary between the sexes, as research shows that males display a greater cannabis-induced high while females’ spatial memory is more likely to be impaired. Men also use cannabis more frequently and in higher quantities and are more likely to use concentrated forms of administration such as blunts or vaporizers while women are more likely to use pipes. Studies also suggest that women are more likely than men to experience serious withdrawal symptoms such as nausea, paranoia, and anxiety.
Cannabis use is especially common among young adults and adolescents and is increasing each year. A 2020 study from the National Institute on Drug Abuse showed that, in 2019, 11.8% of 8th graders reported regular marijuana use in the past year. This grew to 28.8% of 10th graders and 35.7% of 12th graders.
Often, teenagers justify their use of marijuana because of its use for medical purposes. Laws for medical marijuana differ from state to state, and the legislation surrounding it can alter rather rapidly. Children of any age can access medical marijuana if they have a qualifying condition in certain states. However, to date, there is no evidence that medical marijuana is any safer than any other form of marijuana.
There have long been associations between cannabis use and the onset of schizophrenia, and this article will separate the marijuana myths from the facts and explore the connections between cannabis use and psychosis.
Cannabis refers to a group of three plants with psychoactive properties: Cannabis sativa, indica, and ruderalis. The harvesting and drying of the flowers create the form of the drug that is smoked or ingested. The effects of cannabis vary depending on the type, the amount, and the person using it.
Some examples of the perceived “positive” effects of cannabis include:
- Feeling chilled out, blissful, relaxed, and happy
- Laughing, or becoming more excitable or talkative
- Hunger pangs (“the munchies”)
- Altered mind states and mild hallucinations
While marijuana is widely considered to not be physically addictive, regular or heavy users or those who are more susceptible can become dependent and experience withdrawal symptoms such as nausea, insomnia, loss of appetite, irritability, sweating, and diarrhea. If smoked with tobacco, users may also experience nicotine withdrawals.
Adverse consequences of Marijuana use include:
- Impaired short-term memory
- Impaired cognitive functions, including attention, coordination, and judgment
- Increased heart rate
- Anxiety, paranoia
- Impaired respiratory function
- Cardiovascular disease
- Impairments in learning and memory
- Risk of schizophrenia
Cannabis and the Risk of Psychosis
Generally, the adverse effects listed above are short-lasting and dissipate once the effects of the drug have worn off. However, some cannabis users will go on to develop long-lasting or even permanent psychosis.
Cannabis contains two active ingredients called cannabinoids: tetrahydrocannabinol (THC) and cannabidiol (CBD). THC is responsible for the psychoactive effects, and the amount of THC in cannabis is considerably higher today than it was in the 1960s and 1970s, with rates that continue to escalate. THC levels in cannabis have risen from 8.9% in 2008 to 17.1% in 2017, and the mean THC:CBD ratio also rose substantially, from 23 in 2008 to 104 in 2017.
Psychosis is determined by a pattern of unusual thoughts or perceptions, hallucinations, and delusions (believing things that are not really true) and is thought to increase the risk of developing schizophrenia. It is important to note that cannabis use in adolescence is also associated with an increased risk of depression, anxiety, and suicidal ideation. Data from a study conducted in 2018 in Colorado demonstrated increased psychiatric emergency department (ED) visits from adolescents using cannabis and a fivefold higher prevalence of mental health diagnoses within those visits.
It is clear that some people are more susceptible to the harmful effects of cannabis than others based on the following factors:.
- Medical History – If an individual has a predisposition to psychosis due to their personal or family history, then they will be at a greater risk of developing cannabis-induced psychosis.
- Age – Age is an important factor, as teenagers are deemed to be more at risk of developing psychosis than adults. This is either while they are still young or as adults if they starting using as teenagers.
- Genetic – A recently-identified gene, catechol-O-methyltransferase, may make a person more vulnerable to the effects of cannabis. Studies show that those with this gene may have a five times greater risk of exhibiting psychosis and developing schizophreniform disorder than those who do not have it.
Additionally, cannabis increases the risk of a relapse in people who already have schizophrenia, and it can worsen psychotic symptoms.
Conclusion The rapid growth of the cannabis industry, legalization, medical use, and the onset of changes in public perceptions about the risks of cannabis have increased the popularity of this drug among today’s teenagers and young adults. It is imperative that further research is conducted to better understand the effects of cannabis and the associated risks of psychosis. This information must be made publicly available to enable healthcare professionals and policymakers to make informed decisions about the risks of cannabis use and to allow our teenagers to make educated judgements.
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