Despite the increase in data, researchers are still unclear about the effects of combining cannabis and caffeine. However, some evidence suggests there may be risks in mixing these substances.

As more countries legalize cannabis, doctors and researchers are discovering its many effects. They are also learning about the impact of mixing the drug with other substances, including caffeine.

Keep reading to learn more about the risks and effects of mixing cannabis and caffeine.

Cannabis and caffeine on a table.Share on Pinterest
Image credit: Girts Ragelis/Getty Images

Research published in 2014 notes that 85% of the United States population consume at least one caffeinated drink per day. However, beverages are not the only source of caffeine available on the market. Chocolate, dietary supplements, and some plants used as flavorings, such as guarana, also contain the stimulant.

Manufacturers may also add caffeine to food products. To find out how much caffeine a food or beverage product contains, people can check the label on the packaging. The Food and Drug Administration (FDA) state that healthy adults may safely consume 400 milligrams (mg) of caffeine per day.

Although this amount is unlikely to cause side effects, some people may be more sensitive to caffeine. Those affected should consume less to avoid potentially dangerous symptoms.

Caffeine acts as a stimulant, which can make people feel more alert and awake. When someone consumes too much caffeine, they may experience the following symptoms:

Some people consume caffeine for the beneficial effects it may have on concentration, memory, and physical performance.

Epidemiological reports also show a link between chronic caffeine consumption and a lower risk of Alzheimer’s disease or other neurodegenerative diseases.

Other reports suggest caffeine could help prevent motor symptoms and the loss of neurons in people living with Parkinson’s disease.

Experts suggest about 20 million people in the United States use cannabis, with around 1.2 million using medical cannabis.

Cannabis is a complex substance that contains more than 400 compounds, including flavonoids, terpenoids, and cannabinoids. The active ingredient that triggers therapeutic or harmful effects is the cannabinoid family. Each may have a different impact on human health.

One such cannabinoid, tetrahydrocannabinol (THC), is responsible for the psychoactive and therapeutic effects of cannabis. Since THC is the primary psychoactive component within the plant, manufacturers evaluate a cannabis product’s strength according to its THC concentration.

Cannabidiol (CBD) is another cannabinoid found in cannabis. Studies show CBD in small doses may have some stimulant effects. However, at medium to high doses, it may act as a sedative or depressant.

Learn more about CBD and THC here.

A 2016 review suggests acute and chronic cannabis use consistently impair verbal learning, memory, and attention. Further studies are necessary to determine whether people can develop a tolerance to these damaging effects.

Cannabis and caffeine are popular psychoactive compounds, so people likely consume both substances.

In an older preclinical study, researchers demonstrated that THC in cannabis could negatively affect short-term memory in rats. In contrast, caffeine may help enhance short-term memory.

The preclinical study also looked at the combined effects of THC and caffeine in rats. The researchers note that caffeine worsens the memory deficits caused by low doses of THC.

Mixing caffeine and low doses of THC in rats caused similar memory deficits with those produced by higher amounts of THC. In addition, caffeine does not seem to reverse the memory deficits in rats induced by THC.

However, whether combining cannabis and caffeine affects human memory is unknown, and further humans studies are necessary.

Since caffeine acts as a stimulant and cannabis can cause stimulation or inhibition, the immediate effects of mixing cannabis and caffeine may vary between individuals.

Depending on the dose of CBD in a cannabis product, a person may experience a depressive or stimulant effect. Cannabis may, therefore, increase or decrease caffeine’s stimulant effects.

Although there is research looking at caffeine, cannabis, and their individual effects on Parkinson’s disease, studies that evaluate their combined effects are lacking.

Researchers have little experience studying the combined effects of cannabis and caffeine together. Researchers suggest mixing these substances may have significant effects due to the interaction of the adenosine and cannabinoid systems, where caffeine and cannabis act in the body.

These researchers propose that the interaction between cannabis and caffeine may occur in the hippocampus, where receptors for both the adenosine and cannabinoid systems are located. These receptors regulate cognition and memory.

Caffeine may promote cognitive impairment caused by THC found in cannabis. This mechanism may explain the risks of combining cannabis and caffeine. However, further studies are required to confirm these negative effects.

Cannabis and caffeine seem to have opposite effects on memory. People may experience different results when mixing the two substances. Currently, researchers only have theories about their combined effects on humans, as there are not enough studies investigating this.

With the further legalization of cannabis, researchers may have more opportunities to study the risks and effects of cannabis and caffeine.