Key points

  • Cannabis shows promise in treating various symptoms and side effects associated with cancer. Studies also provide some evidence that cannabinoids can prevent cancer from spreading or growing.
  • Approved cannabis medications like dronabinol, nabilone, and nabiximols have all shown some benefits in treating the side effects of cancer and its treatment. Cancer patients who take them, however, report feeling drowsy after dosing.
  • THC and CBD reduce pain, nausea, vomiting and loss of appetite – common cancer symptoms. It also helps reduce anxiety and depression symptoms at lower doses.
  • There is little evidence supporting the idea that cannabis use leads to cancer. However, smoking cannabis with tobacco (a common practice) is associated with higher cancer risk.
  • Despite the potential of medical cannabis in cancer treatment, more research is needed to confirm the benefits of cannabinoids. The current research on medical cannabis for cancer treatment is limited and often has conflicting results.

Cancer is a type of disease in which abnormal cells grow in the body and can spread to other places. It is a complex condition that can be frequently difficult to treat.

Though we have various medications to treat different kinds of cancers, treatment is not always effective. Some cancer medicines also have undesirable side effects that may discourage patients from continuing treatment.

As such, there is a growing interest in other medications – especially those from plant-based sources. Among those is cannabis. For many centuries, cannabis has been used as medicine thanks to its potent cannabinoids.

Several studies suggest that cannabinoids can help treat the many symptoms associated with cancer. Clinical trials show promising results in some cases. Still, it might be too early to tell whether cannabis can be used as a standard treatment for the condition.

This article will provide an overview of medical cannabis for cancer, its benefits, side effects, and what the research has to say.

A brief history of medical cannabis use in medicine

Cannabis is one of the oldest-known traditional medicines used for pain relief, sleep aid, and anti-inflammatory purposes. The plant has been used for thousands of years in traditional cultures around the world for these purposes.

Cannabis has even been found in ancient Chinese texts dating back to 2727 BCE. In fact, records from 2700 BCE describe how doctors were prescribing cannabis to their patients instead of opium.

The plant was introduced to the West in the 1840s as an analgesic and sedative. Historical records show that it was Queen Victoria’s choice of medicine to treat dysmenorrhoea symptoms.

Thanks to changes in legislation, researchers are discovering the potential of cannabis in clinical settings.

Medical cannabis oil: compounds and their effects

Cannabis oil is a concentrated form of cannabis derived from the flowers and leaves of the cannabis plant. It contains high levels of two essential cannabinoids:

  • Delta-9 tetrahydrocannabinol (THC) is the primary psychoactive component in cannabis. It is responsible for the “high” people who smoke cannabis or consume edibles. THC is reported to relieve pain, reduce inflammation, treat nausea, and even act as an antioxidant.
  • Cannabidiol (CBD) is the second most abundant cannabinoid in cannabis. CBD has been shown to have a wide range of therapeutic benefits, including reducing anxiety, inflammation and pain; and increasing sleep quality, mood and memory. Studies and anecdotal evidence suggest that it can also counteract the psychoactive effects of THC.

Though THC and CBD are the most prominent in cannabis, the plant contains nearly 100 other cannabinoids and potentially-therapeutic compounds like terpenes and flavonoids.

How is medical cannabis taken?

There are various ways to take cannabis medically:

  • Via inhalation – Smoking, vaping, and dabbing are all ways to inhale cannabis. THC enters the bloodstream quickly through this method.
  • Via edibles – Cannabis-infused edibles are a popular way to ingest cannabis. The plant’s fat-soluble compounds are absorbed into the bloodstream through digestion and metabolised by the liver first before entering the bloodstream. This process can take up to two hours or more, depending on what you eat.
  • Via medical cannabis oil – Cannabis oil is a concentrated form of cannabinoids that can be ingested orally or sublingually (under the tongue). The effects are reportedly faster and more robust than other delivery methods.

How medical cannabis for cancer can help with cancer symptoms

So far, studies have shown that cannabinoids in medical cannabis play a natural role in pain modulation, control of movement, and mood regulation.

For cancer patients, a large body of both clinical and anecdotal evidence suggests that the plant’s potential lies primarily in symptom management. It can help relieve pain and nausea, reduce anxiety, and boost appetite.

There’s also a growing body of research suggesting that different cannabinoids can cause the following:

  • cell death
  • block cell growth
  • prevent tumour growth
  • reduce inflammation
  • limit the ability of cancer to spread

Approved medical cannabis for cancer

Some cannabis-based products are available on prescription as medicinal cannabis. The following medicines are sometimes prescribed to help relieve symptoms:

  • Nabilone (Cesamet) is a medication developed from cannabis, particularly synthetic THC. It is licensed for treating severe sickness from chemotherapy that is not controlled by other anti-sickness medications.
  • Sativex (Nabiximol) is a cannabis-based medicine that contains synthetically produced THC and CBD.
    It’s licensed in the UK to treat multiple muscle spasticity that hasn’t improved with other treatments. It’s also used for pain linked to cancer.
  • Marinol®/Syndros® (Dronabinol) is a medicine containing THC that’s considered to be less potent than Nabilone. In the U.S., it is prescribed to treat nausea and vomiting after cancer chemotherapy. It’s also been used as an analgesic to help relieve chronic pain.

Medical cannabis can help alleviate cancer-related pain

Alt text: Weak elderly woman with cancer and stomach pain alone at home

Cancer pain results from inflammation, invasion of bone or organs, or nerve injury. It may also occur after surgery, a tumour that presses on nerves, or the destruction of nerves by metastases.

Cancer patients experience various types of chronic pain, including:

  • Bone pain: Pain in the bones is common among cancer patients because they often have to endure multiple surgeries, radiation therapy, and chemotherapy.
  • Neuropathic pain: This type involves damage to sensory neurons in the peripheral nervous system (PNS). The damaged PNS sends abnormal signals to your brain, which causes you to feel numbness, tingling sensations, burning sensations, and/or stabbing pains.
  • Visceral hyperalgesia: This refers to increased sensitivity in internal organs like your lungs and gastrointestinal tract (GI tract).

One study published in the Journal of Clinical Pharmacology reported that patients who took oral THC experienced less pain.

CBD helps with both acute and persistent pain in animal studies. Still, replicating these results with humans leads to inconsistent results.

Medical cannabis for nerve pain and neuropathy in cancer

Several studies show evidence that cannabis can be effective in treating neuropathy. Neuropathy is damage or dysfunction of one or more nerves.

It is a painful condition that can significantly lower one’s quality of life. Nerve pain is common in both cancer and HIV patients.

A few studies have found that smoking cannabis can help this specific type of nerve pain. In Canada, Nabiximols is approved for treating neuropathic pain associated with multiple sclerosis and other cancer-related conditions.

There are also trials examining whether Sativex can help with cancer pain that does not respond effectively to commonly prescribed painkillers. The results of one trial showed that the medication did not improve pain levels. Research, nonetheless, is still ongoing to draw a conclusion.

Many cancer patients use cannabis for anxiety and depression

Aside from physical ailments, cancer patients are prone to developing anxiety and depression. This can make their lives even more challenging and painful.

Cannabis has been shown to be effective in treating these conditions, too. It is used as an anti-anxiety medication for those who have post-traumatic stress disorder (PTSD). In addition, it helps people with anxiety disorders relax and cope better with their condition.

THC and CBD affect the endocannabinoid system, a network of receptors and chemicals in the brain that help regulate mood, sleep, pain perception and appetite. Studies suggest that these compounds in cannabis work by stimulating these receptors to promote feelings of calmness.

However, there are also cases where cannabis can worsen a mental health condition. It’s important to consult with a doctor before taking any steps towards using cannabis for anxiety or depression as a cancer patient.

However, there are also cases where cannabis can worsen symptoms of depression, so it’s important to consult with a doctor before taking any steps towards using cannabis for anxiety or depression.

Medical cannabis treatment improves appetite and food intake

Anorexia, loss of appetite and eventually weight loss are some of the most daunting challenges oncologists face with cancer patients. Currently, few interventions help patients facing nutritional problems.

In a 2006 clinical trial, patients receiving cannabinoids reported improved appetites. According to the patients, food tasted better after taking medical cannabis orally. There’s also anecdotal evidence suggesting that inhaling cannabis can stimulate appetite.

Cannabis treatment can alleviate nausea caused by chemotherapy

Nausea and vomiting related to cancer chemotherapy continue to be significant clinical problems. Although most patients experience mild to moderate nausea, some have severe symptoms that can lead to dehydration or electrolyte imbalances.

Dronabinol and nabilone reportedly have antiemetic (effective against vomiting and nausea) effects. Numerous studies confirm the usefulness of these THC-related medications in the treatment of chemotherapy-induced nausea and vomiting.

Furthermore, a 2006 review published in the Journal of Ethnopharmacology reported that dronabinol leads to better outcomes compared to other medications like chlorpromazine and metoclopramide.

In fact, The National Comprehensive Cancer Network in the U.S. recommends the use of cannabinoids in therapies for chemotherapy-induced nausea.

Medical cannabinoids in cancer therapy

There’s increasing evidence that cannabinoids play a role in cancer therapy. THC and other cannabinoids may inhibit the growth of some tumours.

One study even suggests that a combined dose of THC and CBD enhances the anticancer activity of THC. Furthermore, a THC-CBD dose taken together with the anticancer medication temozolomide leads to a significant reduction of glioma tumour (brain and spinal cord) growth.

There is no reliable evidence that cannabis can prevent cancer, but it may be helpful as a part of a treatment plan for patients who are already diagnosed with cancer. That said, cannabis may not be appropriate for all.

Can cannabis treat different types of cancers? Here’s what we know so far

One of the biggest questions about cannabis for cancer is which types of cancers respond best to cannabinoids.

A 2005 study reported that cannabinoids show potential for colorectal cancer therapy.

In 2021, scientists tested Sativex in combination with the chemotherapy medication temozolomide to treat patients with brain tumours (glioblastoma). More patients survived with treatment compared to the placebo. However, the study is still too small to make any conclusion.

The studies have shown varying results regarding how cannabinoids affect different types of cancer cells and patients’ responses to treatment. Several factors can influence the impact of cannabis on cancer, like:

  • History of cannabis use
  • Tolerance level
  • Type of cancer
  • Amount of THC and/or CBD administered

Possible harmful effects of medical cannabis for cancer patients

Drowsiness is the most common side effect reported in clinical trials with cancer patients. Other common side effects of cannabis use include:

  • anxiety
  • paranoia
  • hallucinations
  • short-term memory loss (this may be worse for people who have never used cannabis before).
  • dry mouth and dehydration

Some patients taking nabilone in studies reported hallucinations. The medications may increase some effects of sedatives, sleeping pills, or alcohol, such as sleepiness and poor coordination.

Cannabis use may lead to dependence on the medication. Those who’ve consistently used cannabis before cancer treatment may also find that it’s less effective for their symptoms.

Because cannabis plants come in different strains and varying levels of active compounds, it can be hard to predict each user’s experience. People also react differently to more standard treatments like cannabis medication.

If you’re on edge about medical cannabis for cancer, consider talking to your doctor. They will be able to help you make an informed decision about cannabis medication and its potential impact on your treatment.

Does cannabis use lead to cancer?

There is little evidence that cannabis itself causes cancer. In fact, many people who smoke cannabis may not know that their cancer risk is higher if they also smoke tobacco with their cannabis.

People who mix tobacco with medical cannabis are at an increased risk for developing lung and head-and-neck cancers compared to those who only use cannabis without smoking.

People who mixed both substances had more than three times the risk of developing lung cancer compared to those who only used medical cannabis by inhalation (such as vaporising or smoking dried leaves).

Conclusion: Is Medical Cannabis Good for Cancer Treatment?

Medical cannabis for cannabis is potentially useful in cancer treatment. Studies show evidence that it can help alleviate the symptoms linked to the complex condition. Currently, there are few cannabis prescription medications used in cancer treatment.

With more clinical trials on the way, medical cannabis may become more common. However, more research is needed before it becomes part of standard treatment.

Remember that cannabis oil for cancer is not a miracle cure. To get the best treatment, discuss all the options available with your doctor. A doctor can also help you decide whether medical cannabis suits your condition.

Frequently Asked Questions (FAQs)

What is the best strain for cancer?

There’s no “best” strain for cancer. Instead, clinicians administer strains that have high THC and considerably CBD content.

Can you take CBD oil with chemotherapy?

Yes, as long as it’s done under the supervision of a doctor.

Can CBD help with chemotherapy side effects?

Studies show that CBD in the form of Sativex can help with chemotherapy-related nausea. As always, consult your doctor before taking any supplements or medications.

Is prostate cancer legal for medical cannabis?

If a licensed doctor merits the use of medical cannabis for prostate cancer, then a patient can get their dose legally.

Do you smoke or eat medical cannabis for lung cancer?

Based on clinical trials, the best way to administer cannabis for lung cancer is via pills or a spray. Smoking could only worsen the symptoms.

References

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