Drinking lots coffee while smoking marijuana can cause people to become more addicted to the drug, according to a new study.

This may be because caffeine enhances the euphoria associated with smoking cannabis.

But scientists say it all depends on how much coffee you drink.

The same research found that small amounts could actually help combat cannabis addiction, by putting you off the drug altogether.

A study by the Integrative National Institute on Drug Abuse in Baltimore found that drinking lots coffee while smoking marijuana can cause people to become more addicted to the drug

‘The discovery does provide some fascinating insights into the workings of the brain, and why humans find coffee and marijuana so enjoyable,’ Dr Gary Wenk, who was not involved in the research, explains on the Oxford University Press' blog.

‘Their euphoric effects might be related to each other.’

A study by the Integrative National Institute on Drug Abuse tested monkeys who were addicted to the active ingredient in marijuana, delta-9 tetrahydrocannabinol (THC).

The monkeys were able to freely self-administer as much or little of THC as they wished.

They found that monkeys that had been given small amounts of the caffeine-mimicking drug were less likely to self-administer THC.

A study by the Integrative National Institute on Drug Abuse tested monkeys who were addicted to the active ingredient in marijuana (pictured), delta-9 tetrahydrocannabinol (THC). They found that monkeys that had been given small amounts of the caffeine-mimicking drug were less likely to self-administer THC

Monkeys that were given a large dose of the drugs - 3 mg, compared to a low dose of 1mg - chose to take more THC.

The study suggests coffee’s addictive properties also involve the brain’s marijuana-like neurotransmitter system.

‘High doses of coffee makes us feel so good because it is able to tap into virtually every reward system our brain has evolved,’ explained Dr Wenk.

DANGERS OF DRINKING ALCOHOL WHILE SMOKING CANNABIS REVEALED Smoking cannabis while drinking alcohol intensifies the ‘high’, according to new research. Inhaling marijuana after drinking increases the concentration of tetrahydrocannabinol (THC), the drug’s main psychoactive ingredient, in the blood, a study found. This raises questions over whether smoking cannabis after consuming even a small amount of alcohol is safe if a person is driving, researchers said. Road traffic crashes rank as the ninth leading cause of death and account for 2.2 per cent of all deaths globally, according to the Association for Safe International Road Travel. In the US, where the researchers carrying out the study were based, cannabis use has surged in the last decade as the drug has been decriminalised in some states so it can be used to treat a range of medical conditions. The researchers said the combination of cannabis and alcohol is most commonly detected after crashes and so they wanted to investigate how mixing the two drugs could affect road safety. Advertisement

‘Hidden within that hot black silken elixir is a chemical that has taken over your brain by mimicking the actions of marijuana.

‘These new studies provide insight into a potential danger of caffeine to increase the addictive and negative cognitive effects of marijuana.’

The researchers added that it’s too early to say whether the same effect occurs in humans as it does in our monkey counterparts.