Pressing, stabbing or pulsating – headaches manifest themselves in different ways. Whether it is a tension headache, migraine or cluster headache, the variants of the disease come with different symptoms. Treatment depends on the type and severity of the pain. What contribution can be done by cannabinoids like THC and CBD? Many studies are not yet available, but some studies give indications of the positive effect of cannabis as a medicine for chronic headaches.
A widespread disease with a high level of suffering
The International Headache Society (IHS) distinguishes between primary headaches and secondary headaches. In primary headaches, the condition is a disease in its own right, as in migraine or tension headache. Secondary headaches are rare. Here, the pain is the symptom of another condition, for example, as a result of a traumatic brain injury.
Cephalgia can be occasional, seizure-like or chronic. Chronic episodes in particular are associated with a severe impairment of the patient’s quality of life and a high level of suffering. In addition, the pain can also be a symptom of a serious disease, such as meningitis. Therefore, the doctor treating the patient must rule out such causes of the disease. If severe headaches occur suddenly and more frequently, those affected should not treat themselves with painkillers, but should first visit a doctor’s office.
The European Headache Federation also offers helpful information for patients on its website
Episodic and chronic tension headache
The most common form of headache is tension headache, followed by migraine. Tension headache is often experienced as a dull, pressing, mild to moderate pain. Episodic as well as chronic tension headaches are treated with classical painkillers. In addition, non-drug treatments such as massage, autogenic training, yoga and other relaxation techniques are helpful.
Tension headache usually does not have just one cause, but is triggered by various factors. For example, this form of the disease is associated with stress, anxiety and depressive moods. However, many sufferers do not suffer from any of these factors.
Migraine is a recurring, one-sided headache. It is often accompanied by nausea, vomiting and sensitivity to noise and light. Sometimes aura phenomena occur before the onset of pain.
Aura describes symptoms that can vary greatly. Affected people experience visual disturbances such as flashes of light, flickering zigzag lines or blind spots in the field of vision. In other migraine patients, the aura manifests itself as weakness, numbness or tingling; there may be disturbances in speech, dizziness or double vision. The aura is only temporary and does not leave any permanent damage.
Women suffer from migraines three times more than men. There are many theories about the cause of the disease, but no clear findings to date. Possible factors that trigger a migraine are:
- Climatic influences: Changes in the weather, coldness
- Certain stimulants such as alcohol, nicotine, citrus fruits, dairy products, chocolate, red wine
- Changes in the sleep-wake rhythm, time shifts, irregular sleep
- Taking hormones
Cluster headache belongs to the group of trigeminal autonomic headaches. It is characterised by severe, unilateral headaches that last between ten minutes and three hours and often start at night. The pain attacks usually occur in the area of one eye. Other symptoms include increased lacrimation and a reddened eye. The attacks occur periodically over weeks (“clusters”) and are followed by a longer symptom-free phase.
Doctors treat an acute attack with medicines like triptans. The active ingredient verapamil is used to prevent the pain attacks. Conventional medicines against pain as well as relaxation techniques do not have sufficient effect on the strong pain attacks of this disease.
Relief through cannabinoids?
Doctors know today that the endocannabinoid system is involved in the body’s central pain processing. Responsible for this is an interplay of endocannabinoids, endocannabinoid receptors and enzymes that produce and break down endocannabinoids in the body.
A 2018 review concludes that the use of cannabis as medicine can prevent the occurrence of pain by increasing the pain threshold. Even if the intensity of the pain is not reduced, it is shown that medicinal cannabis ensures that sufferers subjectively perceive pain as more bearable .
In 2018, American researchers conducted a meta-study to assess the existing medical literature on the use of medicinal cannabis in the treatment of migraine, headaches, facial pain and other chronic pain syndromes . They conclude that there is a growing body of evidence supporting the therapeutic efficacy of cannabis as a medicine in the treatment of migraine and headache.
Most of the existing studies refer to the cannabinoids delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) or cannabis in general. However, the scientists of the meta-study point out that there are many cannabis varieties that differ greatly in their composition of cannabinoids, terpenes, flavonoids and other compounds. These components and their combination produce large differences in benefits and side effects. Therefore, it is important to advance research into the individual medicinal properties of cannabinoids, terpenes and flavonoids in order to be able to optimise cannabis therapies.
Nabilone (a synthetic derivative of THC) has been shown to be an analgesic cannabis-based medicine in a double-blind, placebo-controlled study with 26 cluster headache patients . For the researchers, this study also highlights the potential value of medical cannabis in combination therapy, as an adjunct to traditional therapies or as a treatment option for treatment-resistant cases.
Only few clinical trials available so far
Currently, there is not much evidence from well-designed clinical trials to support the use of medical cannabis for headache. However, there are a large number of patient observations and smaller studies that show efficacy of cannabinoids. Therefore, further research is important to provide evidence for which patients cannabis therapy is appropriate and which cannabis medications are useful .
Headache patients use cannabis
A recent study from Washington State University in 2020 analysed data from a patient app to shed light on the medical efficacy of cannabis for headaches. The researchers used archival data from Strainprint, a medical cannabis app based in the US. This allows patients to track their symptoms before and after using different cannabis strains and doses .
For the analysis, data from over 12,000 sessions in which patients used cannabis for medicinal purposes for headaches were analysed. In addition, data from almost 7,500 sessions in which cannabis was used to treat migraine were assessed. The researchers concluded that individual headache and migraine scores decreased significantly after cannabis use.
Men reported a more significant decrease in pain than women. Taking concentrates brought stronger relief than cannabis flowers. In addition, there was evidence that the effectiveness of cannabis flowers decreased over time and that patients tended to inhale higher doses. According to the scientists, this suggests that tolerance to the effect of cannabis flowers might develop.
Conclusion: Research and the endocannabinoid system
To date, few clinical trials exist that demonstrate clear evidence for cannabis treatment of headache and migraine. Unfortunately, there is a lack of good randomised and placebo-controlled studies to better assess the actual effects of cannabis medicines.
However, doctors nowadays know that cannabinoids influence the functions and activities of signalling pathways that play a key role in pain control. A growing body of laboratory research and preliminary clinical findings indicate that cannabinoids and the endocannabinoid system may be relevant to migraine, tension headache and other forms of headache through multiple mechanisms. Therefore, “the endocannabinoid system qualifies as an interesting area of research worth exploration in the quest for therapeutic targets for the treatment of migraine .”
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