Marijuana’s ability to relieve nausea has been a major highlight of cannabis research over the past few decades. Nausea also happens to be one of the most common reasons for doctors to prescribe marijuana-based pharmaceuticals.
In fact, synthetic THC pills like Cesamet and Marinol have been available since the 1980s for the treatment of nausea, specifically as a side-effect of chemotherapy.
But while nausea associated with chemotherapy is a major concern among doctors and patients alike, there are a variety of other reasons why one might seek treatment for this common ailment.
What Causes Nausea?
Feeling nauseous is a normal human reaction that can be caused by many things. While nausea can be a minor side-effect of various illnesses, it can also be caused by things like anxiety, fear and motion sickness. Nausea is also a natural response to being grossed out.
Gastrointestinal infections and food poisoning are believed to be two of the most common causes of nausea. Others include side-effects of medical interventions as well as early signs of pregnancy (i.e. morning sickness). Furthermore, in approximately 10% of nausea cases, the cause remains unknown.
How Can Marijuana Help?
Nausea was also one of the earliest focuses of modern-day cannabis research, beginning with animal studies in the 1970s. Positive evidence of its cancer applications led oncologists to investigate its effect on chemotherapy-induced nausea through the development and testing of synthetic THC pills. Likewise, early studies compared the effectiveness of oral THC to other anti-nausea drugs, finding that THC was at least as effective as leading anti-nausea drugs of the time, including dopamine antagonists prochlorperazine and metoclopramide.
Successful clinical trials led to FDA approval of two THC-based pharmaceuticals in 1985 – nabilone (sold as Cesamet) and dronabinol (sold as Marinol). Both drugs were approved solely for the treatment of chemotherapy-induced nausea, yet remained infrequently prescribed by oncologists.
The use of THC-based pharmaceuticals experienced further decline in oncology practice as other anti-nausea drugs became more advanced. Interestingly, only one clinical trial was conducted to investigate the effectiveness of oral THC compared with more recently developed drugs, such as the 5-HT3 serotonin antagonist ondansetron. Published in 2007, the study showed that dronabinol was slightly more effective than ondansetron in treating nausea and vomiting in patients undergoing chemotherapy. Of the 64 patients that were studied, nausea was controlled in 71% of those given dronabinol verses 64% of patients given ondansetron and 15% given placebo.
Finally, oral THC has also been suggested as an effective treatment for children experiencing chemotherapy-induced nausea, which is more difficult to control in children than in adults. A study published in 1995 found that Δ8-THC – which is a similar but less psychoactive version of regular THC – was able to control nausea and completely prevent vomiting in children when taken two hours before the start of each cancer treatment. The only reported side-effects were slight irritability.
Medical Marijuana vs. Oral THC
Unfortunately, none of the clinical trials conducted to date have investigated the effectiveness of medical marijuana in the treatment of nausea. Interestingly, many patients seem to prefer medical marijuana to THC-based pharmaceuticals.
Experts have suggested a number of reasons for this:
- Advantages of self-titration with the smoked marijuana
- Difficulty in swallowing the pills while experiencing nausea
- Faster speed of onset for the inhaled or injected THC than oral delivery
- A combination of the action of other cannabinoids with THC that are found in marijuana
CBD and Nausea
Recent evidence of CBD’s ability to reduce nausea provides strong support for the combined action of cannabinoids found in medical marijuana.
Although CBD has yet to be tested on human patients, numerous animal studies have documented its ability to control nausea and vomiting induced by the chemotherapy drug Cisplatin and other toxins such as nicotine, although it failed to reduce nausea related to motion sickness.
Interestingly, CBD’s anti-nausea effects do not seem to be dependent on cannabinoid receptors, but rather inhibition of 5-HT3 receptors – similar to more widely prescribed anti-nausea drugs such as ondansetron. Either way, the fact that CBD is both non-psychoactive and appears to be able to combat nausea suggests that medical marijuana may indeed be a more effective and tolerable treatment for patients suffering from chemotherapy-induced nausea.
What This Means For Your Health
Nausea is one of the major drawbacks of cancer treatment, leading doctors and patients alike to carefully consider the effectiveness of available anti-nausea medications. In this regard, both medical marijuana and THC-based pharmaceuticals appear to be promising treatments, with the latter being more widely accepted in medical practice. However, due to the suggested benefits of using medical marijuana over oral THC, clinical trials are desperately needed.
Unfortunately, there has yet to be research conducted on the use of marijuana for nausea unrelated to chemotherapy, despite the fact that nausea is a widespread ailment among the general public. But until more research is done, it is unlikely that doctors will recommend cannabis to the many patients in need of an effective way of controlling their nausea.