How Cannabis Can Help Nausea
Apr 27, 2020
There is now a consensus among the medical community that cannabis is a helpful treatment for nausea and vomiting. Clinical studies, primarily on patients with cancer, show that cannabinoids like THC and CBD can reduce these challenging symptoms — often better than conventional anti-emetics and with less worrisome adverse effects. In addition, the endocannabinoid system regulates nausea, which explains why cannabinoids are able to impact nausea so strongly. Still, patients should be cautious of cannabinoid hyperemesis syndrome — a rare reaction to heavy cannabis use that actually causes cyclic vomiting and can be fatal to those affected.
Research on nausea and cannabis
The cannabis plant has a long history of being used for nausea and vomiting. In fact, cannabis is one of the oldest known human remedies for nausea and has been used for this purpose for thousands of years. Treatment of nausea was also one of the first medical benefits of cannabis recognized by the modern medical community, and is one of the most well-supported uses for cannabis, based on research.
The main body of research looking at cannabis for nausea comes from studies on cancer sufferers, who often experience severe nausea and vomiting with therapy. There is also positive data on using cannabis for nausea in patients with HIV. Both conditions (and their treatments) can cause severe nausea. Interestingly, treating this nausea was one of the medical uses of cannabis that helped motivate the medical cannabis legalization effort. In fact, treating nausea from cancer and HIV was one of the medical uses for cannabis that spurred on the legalization movement in early years. Doctors in the 1970’s and 1980’s knew that the available options helped patients vomit less, but many still had severe nausea that was resistant to treatment. Symptoms of nausea can be so intense, up to 20% of cancer patients were discontinuing potentially life-saving chemotherapy treatment because of this side effect. When it became clear that cannabis was helping many patients with this debilitating side effect, it pushed researchers to study it in depth and advocate to fight for cancer and HIV patients’ right to use cannabis as a nausea reliever.
Now reviews of the literature confirm that there is substantive evidence that cannabis can aid in nausea relief.
For one thing, the research on cannabis for nausea includes multiple human clinical trials, which show cannabis can be as effective as other modern treatments for nausea — and even more effective than some.
For example, clinical trials on nabilone and dronabinol, synthetic versions of THC (the most common cannabinoid in the cannabis plant) have shown improvement in nausea relief for cancer patients and reduce vomiting episodes significantly. In some cases adding these cannabinoids to the conventional treatment, like dopamine receptor antagonists, improved results, and in other cases switching to cannabinoids alone was more effective than the conventional control.
Other studies show that THC from cannabis can also significantly suppress nausea and vomiting when compared to both placebos and conventional treatments — sometimes matching the efficacy of conventional treatments, and sometimes surpassing them.
Researchers have also looked at Δ8-THC (a cannabinoid similar to THC but with less psychoactive effects) as a nausea reducer in children. This research found that Δ8-THC can also aid in nausea relief by reducing anticipatory nausea, the nausea that occurs from thinking about or encountering something that’s made you sick in the past.
CBD and nausea
CBD (another cannabinoid that lacks THC’s disorienting psychoactive effects) may also be helpful in the treatment of nausea. While human trials have yet to look at CBD alone, a recent animal study suggests that CBD may also relieve nausea and vomiting, as mice treated with CBD showed reduced nausea related behaviors.
In addition, adding CBD to a THC treatment may also be helpful. Often standard anti-nausea drugs only delay nausea rather than eliminating it. One study found that Sativex (a cannabinoid medicine containing an even blend of THC and CBD) taken in conjunction with other anti-emetic therapies, could reduce or eliminate delayed nausea in patients.
Still, it’s notable that some research suggests CBD only helps with nausea in lower doses, and can cause nausea if the dose is too high. Again, we often see this biphasic effect with cannabis and dosing is critical for establishing benefit and avoiding side effects.
How cannabis works on nausea
The endocannabinoid system (ECS) exists in all vertebrates and helps regulate crucial functions such as sleep, pain, and appetite. The human body produces its own cannabinoids, which modulate and activate its various functions, but as its name suggests, the endocannabinoid system can also be modulated and activated by cannabinoids found in the cannabis plant. Because the entire system was only discovered in the past 30 years, scientists still have much to learn about the myriad ways cannabis affects the human body.
Interestingly, nausea is another crucial function that is largely regulated by the ECS, and modulation of this system is the primary way that cannabis can impact our nausea response.
While we have little data from human studies on this, a large body of animal studies have highlighted how this works. One human study that is relevant though, shows that naturally produced cannabinoids in the human body (called endocannabinoids), anandamide and 2-AG, tend to be lower in humans who experience motion sickness. These patients also had less CB1 receptors, a primary receptor in the endocannabinoid system; and inducing motion sickness with parabolic flight maneuvers led to an increase in anandamide early on and an increase of 2-AG later on, suggesting that this system is actively involved in reducing nausea responses.
In animal studies, the connection between the ECS and nausea is even more established. Studies on a wide variety of animals shows that cannabinoids can reduce nausea by stimulating the CB1 receptor. Stimulating CB1 (such as with substances like THC) normally suppresses nausea and vomiting, while substances that cause an opposing activation promote nausea and vomiting.
In addition, CBD seems to work through a different route. It doesn’t interact easily with CB1, but recent studies show that it can stimulate serotonin receptors, which can lead to reduced nausea.
Using cannabis for nausea
When it comes to the practical side of using cannabis for nausea, there hasn’t been much research comparing different ways of using cannabis. Still, research shows positive results for cannabis on nausea whether it is used in edible, sublingual or inhaled formulations. It’s worth noting that many patients say they prefer inhaled methods for nausea, often because it’s easier for patients to find the right dose, it is easier to inhale than eat something when you are feeling nauseous, and it starts working more quickly than edibles. Absorption is also more efficient by inhaling when there are GI issues in general.
One small study compared oral to smoked cannabis and found many patients were able to achieve better results using inhaled cannabis.
When it comes to the cannabinoids to use, most research looks at THC-based cannabis medicines for nausea, so that is the option best supported by the research, but there are also studies showing CBD, a blend of CBD and THC or Δ8-THC could be helpful as well.
One important side effect to mention is that chronic heavy cannabis use can lead to a condition called cannabinoid hyperemesis syndrome, a condition characterized by intractable cyclic vomiting. While rare, it can be fatal if cannabis use is continued, so those using cannabis for nausea should be particularly careful of this side effect. One trait of the condition is that relief can be found from hot baths and showers. If this symptom is experienced, it is a sign that cannabis may be causing additional nausea and vomiting.
In addition, the studies on humans using cannabis for nausea found that common side effects were feeling high, euphoria, dizziness, sedation, depression, paranoia, arterial hypertension and confusion.
The Cannigma content is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Always consult with an experienced medical professional with a background in cannabis before beginning treatment.
Nausea is a feeling of discomfort or uneasiness in the stomach. It can be extremely uncomfortable for many, and may be followed by vomiting though not always.
Nausea is not a condition in itself, but a symptom that can indicate the presence of other conditions, or be provoked reaction to eating, drinking, or inhaling food, medication, or chemicals. Some people experience nausea in response to strong emotions, such as stress, fear, or disgust.
Nausea can continue for days or weeks, and even longer, or be a passing feeling that lasts only a few minutes. The intensity of your nausea can fluctuate over time. Sometimes nausea is accompanied by other symptoms, like headaches or fatigue, depending on the underlying cause.
Nausea is not usually serious, although it’s unpleasant and can impact on your daily life. The best way to treat nausea usually depends on the underlying cause, with treatments ranging from diet and lifestyle changes, to medication, and surgery.
Many people feel nausea at times of extreme stress or fear, or when they smell, see, or taste strong and/or unpleasant smells or foods. Some common medications and therapies can cause nausea, including aspirin, NSAIDs like ibuprofen, oral contraceptives, some narcotics and antibiotics, along with chemotherapy.
Nausea can also affect people with anxiety and depression disorders, and accompany any experience of intense pain. Moreover, people with migraines or other types of pain can experience nausea as well.
Many people feel nausea as part of motion sickness. 50-90% of women experience nausea during the first trimester of pregnancy, and for some, it persists up until giving birth.
Nausea is the earliest symptom of many stomach-related infections, such as food poisoning, gastritis, a stomach ulcer, gastric flu, or eating something that you’re allergic to.
Nausea can also accompany many other conditions, including:
- Gallbladder disease
- Infection of the digestive tract
- Heart attack
- Concussion or traumatic brain injury
- Many types of cancer
- Ulcerative colitis, Crohn’s disease, and irritable bowel syndrome
- Celiac Disease
- Kidney stones
- Post-operative nausea
- Celiac disease
- Menstrual pain
- Aids / HIV
- Alcohol and/or drug addiction
- Neuromyelitis optica
- Ear infections
- Vestibular neuritis
A complete list of conditions that may cause nausea is much more extensive, as it is one of the most common symptoms people have in both acute and chronic conditions.
The best way to treat nausea depends on the underlying cause. Nausea that’s caused by unpleasant sights, tastes, or smells will usually pass once whatever is triggering the nausea has been removed. For many people, it might take some trial and error to work out which food, medication, or environmental pollutants may be the trigger. If you have allergies, it’s best to go to an allergist to get a skin test that checks which substances cause an allergic reaction that can include nausea.
Most of the time, nausea is the symptom of a passing stomach bug, a bout of food poisoning, or other infection in the digestive tract. Usually, you’ll recover from the infection on your own. The most important thing is to remain hydrated, because the vomiting that may accompany nausea in these cases can irritate the stomach and leave you dehydrated.
Other infections and conditions that cause nausea need to be treated with the relevant therapies and medications. Getting the condition under control usually also reduces the nausea.
When nausea is caused by extreme emotions, stress, or anxiety, it can be eased by using therapy to help the body relax and loosen tight muscles in the walls of the stomach. Therapies include:
- Guided breathing techniques
- Tai chi
Whatever the cause, most people with nausea find that it helps to:
- Eat small, light meals
- Avoid heavy, acidic, or spicy foods
- Drink plenty of fluid
- Avoid alcohol
- Add ginger to the food, since ginger reduces nausea
- Rest with the head 12 inches higher than the feet, at least shortly after meals
There are medications called antiemetics that can help reduce nausea, although the choice of the right medication depends on what’s causing the nausea, your overall health, and other medications that you’re taking. Some common antiemetics include:
- Dimenhydrinate (Dramamine) or meclizine, and antihistamines and anticholinergics like scopolamine are good for motion sickness and vertigo, and post-operative nausea.
- Dopamine antagonists like metoclopramide, prochlorperazine, and chlorpromazine are effective for nausea associated with migraine headaches.
- Serotonin antagonists such as ondansetron help with nausea related to gastroenteritis.
- Pyridoxine and doxylamine help with pregnancy-related nausea.
If your nausea continues beyond several days, it is important to seek out medical care as it may be a symptom of a more serious condition that may require treatment.