Medically Reviewed by
Jason Crawford

Article Last Updated on January 17, 2023

Smoking cannabis is a favorite pastime for a lot of cannabis enthusiasts, and even more so after the Covid-19 pandemic started. Drug abuse is at an all-time high, as people are using different coping methods during the lockdown. So, let’s look at cannabis and what effects it has on the human body and mind.

Even though medical marijuana is used to treat or help with several conditions related to chronic pain and mental disorders, some users experience negative side effects from marijuana use, like headaches. 

This article will focus on just that – figuring out whether smoking weed can cause weed headaches, and what relevant studies have to say on the subject.

Cannabinoids and the Effects of Cannabis on Users

The main cannabinoids found in weed that are responsible for the effects that cannabis has on users are tetrahydrocannabinol (THC), responsible for the psychoactive effects, and cannabidiol (CBD), responsible for the anti-inflammatory and calming effects. (National Academies of Sciences, 2017)

The way that these cannabinoids affect users is by binding to the cannabinoid receptors located in the nervous system.  THC stimulates the sympathetic nervous system and it can cause elevated heart rate and blood pressure if consumed in large doses.

While all users experience a different kind of high when consuming cannabis, some of the most common effects of marijuana on users are:

  • Mood changes;
  • Impaired body movement;
  • Increased sensitivity to light, color, sound, touch, taste, and smell.

Some people experience a case of the munchies, euphoria, an increased sense of creativity, although higher doses of cannabis can result in:

  • Impaired memory;
  • Hallucinations and delusions;
  • Psychosis. 

Consequently, dosing cannabis properly is essential to preventing a lot of these side effects, including the ones that are similar to the symptoms of a hangover like fatigue, dry eyes, nausea, brain fog, and headaches.

Can You Get a Weed Headache as a Result of Marijuana Use?

Smoking marijuana, especially long term marijuana use, can cause a list of side effects. Some of them include:

  • Addiction;
  • Poor educational outcome;
  • Altered brain development;
  • Cognitive impairment;
  • Chronic bronchitis symptoms;
  • Increased risk for chronic psychosis disorders.

But, can smoking weed cause a migraine headache?

Facts About Cannabis and Headaches

Not a lot of research suggests that cannabis can cause migraine headaches, and especially not after smoking a single joint. The studies that have been done on marijuana causing headaches, including one done in 1998, don’t link cannabis use to the onset of a headache after smoking. 

However, both the study from 1998 and the one done in 1985 included very small subject groups, so it wouldn’t be accurate to base the conclusion on those studies. On the other hand, various studies have concluded that weed may help treat migraine headaches.

Can Cannabis Help With Headaches?

Newer studies focus on whether cannabis can help with headaches and migraines. A study done in 2018 at the University of Eastern Finland, concluded that cannabinoids may help treat migraine pain as a result of their analgesic, antiemetic, anticonvulsant, and anti-inflammatory effects.

Moreover, a study done in 2020 by the Faculty of Biology Technion at the Israel Institute of Technology, further researched the effects of medical cannabis treatment on decreasing migraine frequency. As endocannabinoids affect serotonin levels, and low or fluctuating serotonin is associated with migraines and headaches, cannabis may help in treating migraines. (Aggarwal et al, 2012; Cutler et al,2020)

Other Possible Causes for Your Headache Instead of Cannabis Use

If you’ve gotten a headache after smoking, vaping, or eating weed, there could be a number of reasons for that. Below, we’ll review some possible causes for headaches after marijuana consumption.

Could Dehydration Be Causing Your “Weed Headaches”?

Consuming weed may result in a list of side effects felt after the initial high wears off, and dry mouth or cottonmouth is one of them. Research shows that cottonmouth occurs as a result of THC binding to the submandibular glands which control saliva production. THC inhibits saliva production, after which dry mouth ensues, so people often mistake this as dehydration.

However, if you don’t hydrate properly while you’re smoking, vaping, or eating cannabis, dehydration can (and probably) will happen anyway, and that may be the reason for your headache – and not cannabis consumption.

Could It Be a Weed Hangover?

A study done in 1985 is probably the only one that connects consuming too much cannabis and experiencing hangover symptoms including a headache the next day. As we’ve talked about this repeatedly on this site, proper cannabis dosing is essential if you want to have a pleasant high. 

The most common residual effects that users experience (like headaches) the next day are often a result of higher doses of marijuana or lack of hydration, so make sure you are hydrated prior to, during, and after consuming marijuana.

Could It Be a Side Effect Caused by Weed Withdrawal?

We’ve covered weed withdrawal in a previous article titled What happens when a stoner stops smoking” where we went over what can happen once cannabis users quit weed. Even though cannabis is not as addictive as drugs like cocaine and opioids, marijuana withdrawal can result in symptoms like headaches, nausea, anxiety, insomnia, and restlessness. Therefore, if you’ve been trying to quit weed as a regular user, your weed headaches may be a result of weed withdrawal.

Could the Headache Be Caused by Laced Weed?

While marijuana users have legal dispensaries in countries where weed is legal, users in countries where weed is still illegal buy cannabis on the black market. The problem with buying weed from dealers is that you can come across laced weed which may be the reason you have headaches after smoking weed. When buying weed on the black market, you should know how to distinguish laced weed from weed that’s safe for consumption. Also, try not to switch your weed dealers too often.

Conclusion on Smoking Weed and Headaches

While there’s no proof that cannabis can cause a headache, other factors related to smoking weed can cause a headache. 

If you are experiencing weed hangover symptoms the next day after a cannabis vape session, your best bet would be to:

  • Hydrate with a lot of water;
  • Eat a healthy and hearty meal;
  • Get some coffee;
  • Massage your temples;
  • Get an OTC painkiller like aspirin or ibuprofen.

For more severe weed withdrawal symptoms, seek medical advice by contacting your healthcare provider. They can give you further information on the best way to detox and mitigate unpleasant symptoms that can happen as a result of withdrawal.

Additional Sources

National Academies of Sciences, Engineering, and Medicine; Health and Medicine Division; Board on Population Health and Public Health Practice; Committee on the Health Effects of Marijuana: An Evidence Review and Research Agenda. The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research. Washington (DC): National Academies Press (US); 2017 Jan 12.   4, Therapeutic Effects of Cannabis and Cannabinoids. Available from: https://www.ncbi.nlm.nih.gov/books/NBK425767/

Aggarwal, M., Puri, V., & Puri, S. (2012). Serotonin and CGRP in migraine. Annals of neurosciences, 19(2), 88–94. https://doi.org/10.5214/ans.0972.7531.12190210

Cuttler, C., Spradlin, A., Cleveland, M. J., & Craft, R. M. (2020). Short- and Long-Term Effects of Cannabis on Headache and Migraine. The journal of pain, 21(5-6), 722–730. https://doi.org/10.1016/j.jpain.2019.11.001

A passionate advocate for the benefits of cannabis. Fraser Horton, who has a background in botany and a strong love of nature, has spent years researching how cannabis affects the body and mind. He established Leaf Nation in 2020, where he has devoted himself to educating people about the legalisation of marijuana and its safe and responsible use. Fraser is committed to highlighting cannabis’ potential for improving wellness and working to dispel the stigma associated with its use.


The information presented on this page is provided as a public service to aid in education and is derived from sources believed to be reliable. Readers are responsible for making their own assessment of the topics discussed here. In no event shall Leaf Nation be held reliable for any injury, loss or damage that could happen if using or abusing drugs.