Maybe you’re having coffee after a joint, or you picked up THC gummies with caffeine in them. Mixing caffeine and weed is common, and more products now combine the two. But the combination isn’t well studied. Here’s what we know about how caffeine and THC interact, the side effects people report and when the combo becomes a problem.
Marijuana and its Effects
Cannabis, also called marijuana, is a plant that contains more than 100 compounds called cannabinoids. The two best known are THC (delta-9-tetrahydrocannabinol), which causes the high, and CBD (cannabidiol), which doesn’t. THC is behind effects like euphoria, anxiety and, at high doses, hallucinations.
THC is also what makes marijuana habit-forming. It triggers the release of dopamine, a brain chemical tied to mood, pleasure, reward and motivation.
People smoke dried cannabis flower, vape it, use concentrates (dabs) or eat it in edibles and drinks.
Related reading:
- Long Term Cognitive Effects of Marijuana Use
- Fact or Fiction: Marijuana Kills Brain Cells
- Mixing Weed & Antidepressants
Caffeine and its Effects
Caffeine, a natural stimulant of the central nervous system (CNS), is known to prevent drowsiness by blocking the action on receptors of adenosine. It also increases energy and decreases drowsiness. You can find caffeine in many substances such as coffee beans, tea leaves and kola nuts.
Synthetic caffeine can also be used in medicine, food, and beverages. Synthetic caffeine is found in many pain relievers, cold medications, and other over-the-counter energy-boosting medicines.
Energy drinks such as Red Bull and Bang, plus some energy gums and snacks, contain added caffeine. According to the FDA, energy drinks can have anywhere from 54 to 328 mg of caffeine per 16 ounces. Healthy adults can generally have up to 400 mg a day without negative effects, which is about two to three cups of coffee. One large energy drink can get you most of the way there, before you add THC to the mix.
Caffeine can have side effects that may include:
- Increased energy
- Diminished drowsiness, sleepiness
- Urination
- Heartburn
- An increase in blood pressure
A caffeine overload can be identified by:
- Restlessness
- Shakiness and jitteriness
- Trouble sleeping or insomnia
- Headaches
- Dizziness
- Rapid heart rate
- Dehydration
- Anxiety
Regular use can also lead to dependence: needing more for the same effect, or getting headaches without it.
What Happens When You Mix Weed and Caffeine?
Caffeine and THC act on different systems in the brain, which is why mixing caffeine and weed is hard to predict.
Older studies have shown that THC in cannabis can negatively impact short-term memory in rats. However, caffeine has been shown to increase short-term memories. Preclinical studies also examined the effects of caffeine and cannabis on rats.
Combining low doses with caffeine and marijuana produced memory deficits comparable to those experienced by rats who were given high doses. THC-induced memory deficits were also not reversed by caffeine. [1]
Because caffeine is a stimulant, and cannabis can cause stimulation or inhibition, individual effects may differ. People have reported anxiety, paranoia, hallucinations, and other unpleasant side effects from marijuana use. The combined effects of caffeine and cannabis products such as coffee can cause unpredictable results.
Side effects people report from caffeine and marijuana include:
- Heart rate increases
- Headache
- Paranoia
- Anxiety
- High blood pressure
- Confusion or disorientation
- Impaired judgment
- Upset stomach
These effects may come down to how two brain systems interact: the adenosine system, where caffeine works, and the cannabinoid system, where THC works. [2]
The interaction of the two substances could occur in the hippocampus. This is the area of the brain that houses receptors for the cannabinoid and adenosine systems. The brain’s hippocampus plays an important role in memory and learning. [2]
Combining cannabis with caffeine may cause cognitive impairment. This mechanism could explain the potential dangers of cannabis-caffeine combination, but further research is needed to confirm it.
Help for Cannabis Addiction
Caffeine and weed each affect memory, and together their effects are hard to predict.
Long-term marijuana use can lead to cannabis use disorder, a medical condition where you keep using even when it causes problems. You might need weed to sleep, eat, relax or get through the day, and feel irritable or restless without it.
Weed bought off the street can also be laced with or replaced by synthetic cannabinoids, which carry serious risks. Learn how to tell if weed is synthetic.
If you or someone you love is struggling, you’re not too far gone. Many of us sat where you’re sitting. All In Solutions has treatment centers in California, Florida and New Jersey. Learn how our marijuana addiction treatment works.
Check my insurance or Call admissions now at 855-762-3796.
Caffeine and Weed FAQs
Does caffeine make a weed high stronger?
It might, but the research is thin. Most of what we know about caffeine and THC comes from animal studies, not people. In one study with rats, low doses of THC combined with caffeine caused memory problems similar to those from higher doses of THC alone. That suggests caffeine may make some THC effects stronger. Caffeine also won’t sober you up: in the same research, it didn’t reverse THC’s effects on memory. How the mix hits you depends on how much of each you take, the product (a joint, a vape or THC gummies) and your tolerance.
Is it safe to drink coffee after smoking weed?
There’s no clear answer, and that’s the problem. Plenty of people do it, but no research shows that caffeine and marijuana together are safe. Caffeine is a stimulant. Cannabis can speed you up or slow you down, so the combination is hard to predict. Common side effects include a racing heart, higher blood pressure, anxiety and paranoia. Your risk goes up if you have a heart condition, high blood pressure or an anxiety disorder, or if you’re pairing strong edibles with energy drinks. If you’re using weed or caffeine to manage anxiety, our anxiety and addiction treatment team can help you sort out what’s driving it.
Can caffeine and THC raise your heart rate?
Yes. Each one can raise your heart rate on its own, and together the effect may add up. Caffeine can also raise blood pressure. A pounding or racing heart is one of the side effects people report after mixing caffeine and weed, often with anxiety. Call 911 if you have chest pain, trouble breathing, fainting or a heartbeat that won’t slow down.
Is caffeine and weed a bad combo?
For some people, yes. And no one can promise it’s harmless for anyone. Caffeine is a stimulant, and cannabis can speed you up or slow you down, so mixing caffeine and weed is hard to predict. The combo is riskier if you:
- Have a heart condition or high blood pressure
- Live with anxiety or panic attacks
- Use strong products, like THC gummies or edibles, with energy drinks
- Take other medications, including antidepressants (see how weed and antidepressants interact)
