Marijuana users feel MORE pain, study debunks theory cannabis numbs discomfort

Marijuana users feel more pain, new research suggests.

After an injury, people who use cannabis require higher doses of painkillers than non users, a US study found.

Although previous research suggests marijuana eases pain, the drug is illegal in the UK and many US states, and is therefore not widely used in hospitals. 

Addicts may therefore experience withdrawal while in hospital that worsens their discomfort, according to the researchers.

Washington, Oregon, California, Alaska and Colorado have legalised marijuana for medical or recreational use. 

Marijuana users feel more pain and require higher painkiller doses, research suggests (stock)


Going from being an occasional marijuana user to indulging every day increases the risk of psychosis by up to 159 percent, research revealed in July 2017.

Marijuana is thought to cause psychosis-like experiences by increasing a user’s risk of depression, a study found. The two mental health conditions have previously been linked.

Frequently abusing the substance also significantly reduces a user’s ability to resist socially unacceptable behavior when provoked, the research adds.

Study author Josiane Bourque from the University of Montreal, said: ‘Our findings confirm that becoming a more regular marijuana user during adolescence is, indeed, associated with a risk of psychotic symptoms. 

‘[Psychosis symptoms] may be infrequent and thus not problematic for the adolescent, when these experiences are reported continuously, year after year, then there’s an increased risk of a first psychotic episode or another psychiatric condition.’ 

The researchers, from the University of Montreal, analyzed around 4,000 13-year-olds from 31 high schools in the surrounding area.

Every year for four years, the study’s participants completed questionnaires about any substance abuse and psychotic experiences.

Psychotic symptoms included perceptual aberration – for example feeling that something external is part of their body – and thinking they have been unjustly badly treated.

The participants also completed cognitive tasks that allowed the researchers to assess their IQ, memory and stimuli response. 

How the research was carried out   

The researchers, from the Swedish Medical Center, Colorado, analysed around 260 people who were involved in minor vehicle accidents and admitted to trauma centres. 

Of these, 54 tested positive for recent marijuana use while 16 claimed they used the drug more or less every day.

Around nine percent of the participants tested positive for other prescription or illegal drugs, such as cocaine and opiates.

Severe pain may prolong patients’ hospital stay 

Results suggest marijuana users require 7.6mg of opioid painkillers a day in hospital compared to 5.6mg for non-drug users.

On a scale of zero-to-10, with 10 being the worst, people who take cannabis rate their daily pain as 4.9, compared to 4.2 for non users. 

This could cause marijuana users to stay in hospital longer because ‘we don’t want to discharge them on massive doses of narcotics’, according to Dr Anne Wagner, from the UCHealth Burn Center, Colorado, who was not involved in the study.

Users may also experience drug withdrawal, such as nausea and vomiting, which can delay healing.

Other prescription or illegal drugs do not have the same effect on users’ pain levels.  

‘A lot of people think marijuana is harmless’ 

Speaking of the findings, Dr Wagner said: ‘I really think a lot of people think [marijuana is] very harmless.

‘I don’t think they’re at all aware about how much it’s going to affect them in their recovery.’

Lead author Kristin Salottolo added: ‘Marijuana users in need of pain control deserve special consideration when selecting the dosage and frequency of narcotics [painkillers]’.

The researchers add further studies are required to determine how best to ease discomfort in cannabis users.  

The findings were published in the journal Patient Safety in Surgery.