The medical knowledge about the various possible uses for cannabis is highly controversial. It is good for nausea and vomiting in cancer chemotherapy, loss of appetite and wasting in HIV / AIDS, chronic, especially neuropathic pain and spasticity in multiple sclerosis and paraplegic diseases, but rather bad in other diseases such as epilepsy, pruritus and depression.
However, the level of scientific knowledge about specific indications does not necessarily reflect the actual therapeutic potential of the disease.
- Nausea and vomiting.
The side effects of cancer chemotherapy are the most researched indication: about 40 studies (THC, nabilone, cannabis), especially in the 1980s. THC should be taken in relatively high doses so that psychological side effects are relatively common. THC is inferior to metoclopramide at high doses. There is no comparison with one of today’s specific serotonin antagonists. Some recent studies have shown that low doses of THC improve the effectiveness of other nausea medications when taken with them. In folk medicine, cannabis products are also used in other forms
nausea, especially with AIDS and hepatitis.
- Loss of appetite and exhaustion.
The appetite-stimulating effect is already observed with daily doses of 5 mg THC. If necessary, the dosage can be increased to 20 mg per day. In a long-term study of 94 AIDS patients, the appetite-stimulating effect of THC was maintained compared to the increase in appetite in a six-week study. Compared to placebo, THC doubled the appetite. Patients tended to maintain a stable body weight for at least 7 months. It also reported a positive effect on weight in 15 Alzheimer’s patients who refused to eat. Surprisingly, confusional behavior was also reduced with the THC supplementation compared to the placebo.
In many studies with THC, nabilon and cannabis, good effects on spasticity have been observed in the context of multiple sclerosis and cross-disease. Other positive symptoms included pain, paresthesia (abnormal sensations), tremors, and ataxia. Several studies have also shown improved control of bladder function. There are isolated reports of the beneficial effects of cannabis on spasticity, even when the brain is damaged.
- Movement disorders.
There is some positive experience with cannabis treatment for Tourette’s syndrome, dystonia and tardive dyskinesia, as well as the first controlled trials for use in Tourette’s syndrome. Most patients may experience slight improvement, but some may have exceptionally good complete control of symptoms. After taking THC, some MS patients had anti-attack effects and reduced tremors. Despite some positive reports, no objective success has been found in the treatment of Parkinson’s and Huntington’s diseases. However, cannabis products can be used for movement disorders caused by L-Dopa in the context of Parkinson’s disease, without worsening the underlying disease.
- Pain symptoms.
Large clinical studies have demonstrated the pain relieving properties of cannabis products. Potential indications include neuropathic pain in multiple sclerosis, damage to the plexus of the arms and HIV, pain in rheumatoid arthritis, cancer pain, headache, menstrual pain, chronic intestinal inflammation, and neuralgia. A combination with opiates is possible.
In 1971, when the effects of cannabis on healthy cannabis users were systematically recorded, the effect of lowering intraocular pressure was discovered. Over the next 12 years, a number of studies were carried out on healthy volunteers and glaucoma patients using cannabis and various natural and synthetic cannabinoids. Thereafter, smoking cannabis and oral administration of THC in doses of 10-20 mg lower intraocular pressure by an average of 25-30%, sometimes by 50%. Presumably, some non-psychotropic cannabinoids and, to a lesser extent, some non-cannabinoid components of the cannabis plant also have the effect of lowering eye pressure.
Animal studies have shown the antiepileptic effect of some cannabinoids. The antiepileptic effects of phenytoin and diazepam were enhanced by THC. Its use in epilepsy has historically been one of the oldest traditional indications. According to several case reports from the 20th century, cannabis is still a vehicle for some generalized epilepsy patients today to control uncontrolled seizure disorder. Cannabis also occasionally exhibits pro-convulsive effects.
Most studies dating back to the 1970s are of an acute nature. The effects of a cannabis cigarette (2% THC) or oral THC (15 mg) are roughly equivalent to clinical doses of known bronchodilators (salbutamol, isoprenaline). Oral cannabis products should be preferred due to the damaging effects on the mucous membrane. In some cases, after inhalation, a reflex narrowing of the bronchi was observed.
- Addiction and withdrawal symptoms.
According to historical reports and some case reports, cannabis is a good treatment for benzodiazepine withdrawal symptoms, opiate and alcohol dependence. Therefore, it is often referred to as an exit drug. Reducing the physical symptoms of withdrawal as well as reducing the stressful feelings associated with quitting drugs can play a role here.
- Psychiatric symptoms.
In various studies, the effect of improving mood in reactive depression has been repeatedly observed as a side effect of dronabinol treatment. There are several reports in the literature of cases of other mental illnesses or symptoms such as sleep disturbances, anxiety disorders, bipolar disorders, and endogenous depression. Different authors have formulated different views on the psychiatric syndromes associated with cannabis. While some tend to emphasize the problems caused by cannabis, others tend to emphasize therapeutic possibilities. It is possible that cannabis products – depending on the case – can be beneficial or harmful in the case of mental illness, so the doctor and patient must be self-critical and open to both possibilities.
- Autoimmune disease and inflammation.
For a number of inflammatory pain syndromes (eg ulcerative colitis, arthritis), cannabis products can have both analgesic and anti-inflammatory effects. For example, patients report a reduced need for steroidal and non-steroidal anti-inflammatory drugs. There are also reports of positive effects of cannabis self-medication for allergies. It is unclear if cannabis products may have a significant effect on the causative processes of some autoimmune diseases.
- Various mixed symptoms.
There are a number of positive reviews for many indications that cannot be attributed to the groups mentioned above, such as itching, hiccups, ADD (attention deficit disorder), high blood pressure, tinnitus, chronic fatigue syndrome, restless legs syndrome and others. At the moment, various authors have described several hundred possible indications for the use of cannabis or THC. For example, 2.5 to 5 mg of THC was effective in relieving pruritus in liver disease in three patients. Another example is the successful treatment of chronic hiccups (singultus) in a patient who suffered from a fungal infection of the esophagus and who developed persistent hiccups after surgery. No medicine was effective. However, smoking cannabis completely relieved the symptoms.
Cannabis products, as expected, have been shown to often perform particularly well in multisymptomatic diseases that fit the spectrum of THC activity, such as pain disorders with an inflammatory component (such as arthritis) or increased muscle tone (such as menstrual cramps, spasticity of the spine) or for painful conditions with Nausea and loss of appetite, possibly with additional pain and / or anxiety or depression (eg, AIDS, cancer, hepatitis C).