Cannabis in cancer therapy – a topic that raises many questions. We clarify what medical cannabis can achieve in cancer treatment, where it is used, and what affected individuals should consider. Without promises of a cure, but with clarity.
What is medical cannabis and how does it work?
Medical cannabis refers to cannabis flowers or extracts used by prescription to treat symptoms. Unlike over-the-counter hemp products, they are subject to strict pharmaceutical standards and contain defined amounts of active ingredients. The plant itself contains over 100 different cannabinoids – two of which are the focus of medical application.
The most important cannabinoids: THC and CBD
THC (Tetrahydrocannabinol) is the best-known cannabinoid. It has psychoactive effects and can relieve nausea, stimulate appetite, and alleviate pain. CBD (Cannabidiol), on the other hand, does not cause intoxicating effects. It is attributed with calming and anti-inflammatory properties. In medicinal preparations, both active ingredients are used individually or in combination – depending on the indication and individual tolerance.
How cannabis works in the body
Our body has its own endocannabinoid system. It consists of receptors located in the brain, nervous system, immune cells, and other tissues. Cannabinoids from the plant bind to these receptors and can thus influence various processes – from pain perception and appetite to inflammatory reactions. The effect is complex and individually different.
Difference from over-the-counter hemp products
Over-the-counter CBD oils or hemp teas usually contain only traces of THC and are not subject to pharmaceutical control. Medical cannabis, in contrast, is produced in standardized quality, lab-tested, and precisely dosed. Access is exclusively by medical prescription. This distinction is important – not every hemp product is suitable for therapeutic purposes.
Use of cannabis in cancer treatment
In oncology, medical cannabis is not used to treat the tumor itself, but to alleviate accompanying symptoms. It is about quality of life, not cure. Its use is usually complementary to conventional therapy – for example, during chemotherapy or in palliative care.
Relief of nausea and vomiting
Chemotherapy causes severe nausea in many affected individuals. THC-containing cannabis can be supportive here. Studies show that in some cases, it can help when conventional antiemetics are not sufficiently effective. The effect usually occurs within one to two hours. Not all patients respond to it – individual tolerance must be checked.
Appetite stimulation and weight maintenance
Weight loss is a common side effect of advanced cancer. THC can stimulate appetite and thus help to maintain strength. This effect is well-documented, but not all affected individuals perceive it equally strongly. Dosing must be done carefully to avoid unwanted psychoactive effects.
Pain therapy for cancer
Chronic pain is one of the most burdensome symptoms. Cannabis can play a supplementary role in pain therapy – especially for neuropathic pain, which often responds poorly to classic painkillers. The data situation here is not yet conclusive, but initial experiences are promising. A combination with other analgesics is possible and frequently practiced.
What does the research say?
The scientific data on cannabis in cancer therapy is growing but still incomplete. Many studies are small, methodologically diverse, or refer to individual symptoms. Large, controlled long-term studies are still lacking. Nevertheless, there are indications that can justify its use in certain situations.
Current study situation at a glance
Several positive studies exist for the relief of nausea and vomiting during chemotherapy. There is also evidence for appetite stimulation. For pain, the evidence is mixed – some studies show improvements, others no significant effects. Important: Cannabis is considered a supportive therapy in research, not a substitute for established procedures. Most data come from observational studies or smaller clinical trials.
Limitations and open questions
Whether cannabis can directly influence tumor growth is not scientifically proven. While laboratory experiments on cell cultures show interesting effects, these cannot be transferred to humans. Interactions with other medications have also not yet been fully researched. Individual reactions vary greatly – what helps one patient may be ineffective for another. Serious research remains cautious and speaks of possible effects, not guarantees.
Access and practical advice
Anyone considering medical cannabis needs medical supervision. Access has been eased in Germany since 2017 but remains subject to clear conditions. Transparency and open communication with the treating team are crucial.
Prescription and legal framework
Medical cannabis can be prescribed if other therapies are not sufficiently effective or are not tolerated. The decision lies with the doctor. Approval by the health insurance company is required in many cases but is not always granted. The costs can be considerable. Important: There is no legal entitlement to cannabis as medicine – the prescription is made after individual review.
Forms of administration and application
Medical cannabis is available as flowers for vaporization, as extracts, or in the form of finished medicinal products such as Dronabinol or Sativex. The choice depends on symptoms, tolerance, and personal preferences. Vaporization works quickly, extracts offer more consistent dosing. Adjustment is gradual – start low, increase slowly. Patience is required until the right dose is found.
What affected individuals should pay attention to
Openness towards the treatment team is central. Interactions with other medications must be clarified. Side effects such as fatigue, dizziness, or dry mouth can occur. Driving may be restricted. Also important: cannabis is not a miracle cure. It can alleviate symptoms but does not replace established cancer therapy. Realistic expectations and close coordination with specialists create the best basis for meaningful use.