Diseases, cannabis and side-effects

Diseases, cannabis and side-effects

General remarks

In general CBD is remarkably safe compared to almost all conventional drugs. CBD holds no fatal side-effects, the most common side-effect is dry mouth. CBD is very anti-inflammatory and work as an anti-psychotic molecule.

Clinical studies with single cannabinoids or whole plant preparations (smoked cannabis, cannabis extract) have often been inspired by positive anecdotal experiences of patients employing crude cannabis products. The anti-emetic, the appetite enhancing, relaxing effects, analgesia, and therapeutic use in Tourette’s syndrome were all discovered in this manner.

Given the increasing evidence on the therapeutic potential of different cannabinoids, it is important to distinguish between medical usage of products that are rich in THC and those that are rich in the CBD, which is a non-psychoactive ingredient of cannabis.

There is no death due to cannabis and practically no side effects associated with CBD, those that have been registered with Epidiolex: (along with other medicines)

In Denmark 21 side-effects have been reported during the first year of the trial, 5 (4 Bedrocan, 1 drops Stenocare) was considered serious. In most cases people overdosed. 1800 patients got their medical cannabis from the doctor, during the same period.

General Remarks (side-effects)

Deaths due to cannabis use are not known. The median lethal dose in rats was 800 to 1,900 mg (depending on the strain) oral THC per kilogram body weight. In studies with monkeys, no deaths were recorded following the highest applied doses of 9,000 mg/kg oral THC. All possible side effects are dose dependent. Therapy should start with low doses, slowly increasing, so that the individual dose can be determined and unwanted effects can be avoided.

Doctor Tina Ingrid Horsted: "Our study shows that medical cannabis is a harmless alternative to traditional painkillers. Most had mild side effects in the form of mental and physical fatigue". Tina has not experienced any of her patients becoming addicted to cannabis as a medicine. But they are addicted to morphine. (+400,000 Danes on morphine, the 40,000 are addicted) She estimates that about 10-20% of Danes have tried to self-medicate with cannabis - either by smoking or taking the oil.

Acute side effects

Known psychic side effects are sedation, euphoria ("high"), dysphoria, fear to die, feeling to lose control, impairment of memory, altered time perception, depression, hallucinations. In case of strong psychic side effects, the affected should be brought to a calm place and "talked down". Cognitive and psychomotor performance are attenuated. A discrete reduction of psychomotor performance may be observed up to 24 hours after the administration of THC.

Frequent acute physical side effects are dry mouth, movement disorder, muscle weakness, slurred speech, the increase of heart rate, the decrease of blood pressure in the vertical position, eventually with dizziness. In the case of dizziness, the affected should lay down. In the horizontal position, a slightly higher blood pressure may be measured. Rare side effects are nausea and headaches.

All acute side effects are dose-dependent and generally disappear within hours or 1-3 days without specific treatment.

Cannabis (THC) possesses a potential for addiction. Dependency may not be a relevant problem within the bounds of therapy of diseases, but withdrawal may be unwanted. Withdrawal has not been described in patients that were long-term treated with THC. But withdrawal has been observed in recreational users. Thereby psychic symptoms (anxiety, restlessness, insomnia) and physical symptoms (salivation, diarrhoea) may occur. The course of a psychosis may be influenced unfavorably. Invulnerable persons the onset of a psychosis may be accelerated or triggered.


Cannabis may be beneficial in patients suffering from ADHD (attention deficit hyperactivity disorder).

AIDS – see HIV




Clinical studies have shown that cannabis may not only increase appetite in patients with Alzheimer’s disease but also reduce disturbed behavior and agitation. A small study reported that cannabis oil was effective in treating symptoms of dementia patients, including agitation/aggression, irritability, apathy, sleep, and caregiver distress.

An appetite enhancing the effect of THC is observed with daily divided doses totaling 5 mg. When required, the daily dose may be increased to 20 mg. In a long-term study of 94 AIDS patients, the appetite-stimulating effect of THC continued for months, confirming the appetite enhancement noted in a shorter 6-week study. THC doubled appetite on a visual analog scale in comparison to placebo. Patients tended to retain a stable body weight over the course of seven months. A positive influence on body weight was also reported in 15 patients with Alzheimer’s disease who were previously refusing food. In addition, cannabis products can improve appetite in cancer patients and in chronic obstructive pulmonary disease (COPD). A study, with a small sample size, points to the potential of THC for improvement of symptoms associated with Anorexia Nervosa.

Appetite stimulant


5 best strains artritis


Experiments examining the anti-asthmatic effect of THC or cannabis date mainly from the 1970s, and are all acute studies. The effects of a cannabis cigarette (2% THC) or oral THC (15 mg), respectively, approximately correspond to those obtained with therapeutic doses of common bronchodilator drugs (salbutamol, isoprenaline). Since inhalation of cannabis products may irritate the mucous membranes, oral administration or another alternative delivery system would be preferable. Very few patients developed bronchoconstriction after inhalation of THC.



Cancer – breast

Cancer- colorectal

Cancer - glioma / brain

Cancer - leukemia

Cancer - lung

Cancer – oral

Cancer - pancreatic

Cancer – prostate

Cancer – skin - melanoma

Cancer – risk cannabis vs tobacco

Cancer - skin

Cancer – testicular

Cancer –various/ unnamed

Cannabidiol (CBD)

Chemical composition



Chronic cystitis




Dependency and Withdrawal

According to historical and modern case reports cannabis is a good remedy to combat withdrawal in dependency on benzodiazepines, opiates and alcohol. For this reason, some have referred to it as a gateway drug back. In this context, both the reduction of physical withdrawal symptoms and stress connected with the discontinuance of drug abuse may play a role in its observed benefits. In addition, a small study suggests that CBD may be helpful in the treatment of tobacco dependency





Endocannabinoid system and endocannabinoid deficiency


Fibromyalgia is a painful condition affecting mostly women. While doctors don’t know much about the condition, some researchers believe it could be related to an endocannabinoid deficiency.

Studies suggest that cannabinoids can reduce pain that is similar to the pain of fibromyalgia. Other studies have shown that blocking cannabinoid receptors results in pain — meaning that an endocannabinoid deficiency could potentially cause pain like in fibromyalgia.

Additionally, many people report that the cannabinoids in marijuana are helpful as a treatment for fibromyalgia.


Migraine headaches are extremely painful and can often disable a patient for days at a time.

Migraines are associated with changes in the neurotransmitter serotonin. The endocannabinoid system and the serotonin system are
strongly linked, leading researchers to propose that migraines result from an endocannabinoid deficiency.

Researchers believe cannabis could be an effective treatment for migraine, because it has a unique set of effects on the brain that make it an “ideal treatment” for the condition.

Irritable Bowel Syndrome

IBS is a condition that causes diarrhea, constipation, and abdominal pain. It is surprisingly common, with estimates that it affects around 15% of the population. Cannabinoid receptors are expressed in the gut, and function to regulate gastrointestinal motility, or how fast food moves through the intestines. Symptoms of IBS are related to motility that is either too fast in the case of diarrhea, or too slow in the case of constipation.

Marijuana is often used as a treatment for IBS symptoms, and has been used to treat diarrheal illness such as cholera in the past. While there are not many studies on the link between the endocannabinoid system and IBS, researchers believe endocannabinoid deficiency theory could help explain the disorder.


A 2013 study found that endocannabinoid levels were reduced in PTSD patients, but not controls. The researchers measured blood levels of 2-AG and anandamide in people closely affected by the 9/11 attacks on the World Trade Center. They found that 2-AG levels were significantly reduced in those who met diagnostic criteria for PTSD, but not in those who did not.

This supports the theory that PTSD could be related to a clinical endocannabinoid deficiency.


The use in epilepsy is among its historically oldest indications of cannabis. Animal experiments provide evidence of the antiepileptic effects of some cannabinoids. The anticonvulsant activity of phenytoin and diazepam have been potentiated by THC. According to a few cases reports from the 20th century, some epileptic patients continue to utilize cannabis to control an otherwise unmanageable seizure disorder. Cannabis use may occasionally precipitate convulsions. A few studies showed that the use of CBD-enriched extracts by children and adolescents with intractable epilepsy yielded a positive effect on seizure load. Improvement in other symptoms, such as behavior, communication, motor skills and language, were also observed.

Elderly people

Familial mediterranean fever




Research shows that cannabinoids – the active compounds present in the cannabis plant – can have a beneficial effect on fibromyalgia symptoms by reducing pain and improving sleep quality. Although cannabis has not been established as an approved medicine for this medical condition, surveys indicate that fibromyalgia patients already self-medicate using cannabis. Moreover, some patients have reported cannabis to produce fewer side-effects than the available conventional treatments and, most importantly, to be effective.

Gateway Theory


In 1971, during a systematic investigation of its effects in healthy cannabis users, it was observed that cannabis reduces intraocular pressure. In the following 12 years, a number of studies in healthy individuals and glaucoma patients with cannabis and several natural and synthetic cannabinoids were conducted. Cannabis decreases intraocular pressure by an average of 25-30%, occasionally up to 50%.

Some non-psychotropic cannabinoids, and to a lesser extent, some non-cannabinoid constituents of the hemp plant also decrease intraocular pressure. While in most western countries there are other medications for intraocular pressure that are available to patients, in other parts of the world this may not be the case.

Gynocology and obstetrics

Heart Disease/ Cardiovascular





Historical studies


Huntington’s disease


Idiopathic Intracranial Hypertension

Inflammatory bowel disease and irritable bowel syndrome

Following the rationale that the endocannabinoid system is involved with immunity and inflammation, several studies have shown that cannabis may have a therapeutic effect for treatment of patients with Inflammatory Bowel disease (Crohn’s disease and ulcerative colitis). Studies demonstrated that cannabis-based products, especially with THC content, were able to improve clinical outcomes of patients, including appetite stimulation, weight gain, reduction of pain and significant improvement in disease activity. Some patients achieved remission of the disease, and other were able to reduce the consumption of medications, such as steroids.

One study demonstrated a therapeutic effect of oral THC (dronabinol) for specific sub-groups of patients with irritable Bowel disease (IBS-D and IBS-A), and showed improved colonic compliance and motility.


Marinol / synthetics / cannabinoid mixtures

Meige’s syndrome

Migraine / Headache

Morning Sickness

Mortality Rates


In many clinical trials of THC, nabilone and cannabis, a beneficial effect on spasticity caused by multiple sclerosis or spinal cord injury have been observed. Among other positively influenced symptoms were the pain, paraesthesia, tremor and ataxia. In some studies improved bladder control was observed. There is also some anecdotal evidence of a benefit of cannabis in spasticity due to lesions.

In a number of painful syndromes secondary to inflammatory processes (e.g. ulcerative colitis, arthritis), cannabis products may act not only as analgesics but also demonstrate anti-inflammatory potential. For example, some patients employing cannabis report a decrease in their need for steroidal and nonsteroidal anti-inflammatory drugs. Moreover, there are some reports of positive effects of cannabis self-medication in allergic conditions. It is as yet unclear whether cannabis products may have relevant effects on causative processes of autoimmune diseases.of the brain.



Treatment of side effects associated with antineoplastic therapy is the indication for cannabinoids which has been most documented, with about 40 studies (THC, nabilone, other THC analogues, cannabis). Most trials were conducted in the 1980s. THC has to be dosed relatively highly, so that resultant side effects may occur comparatively frequently. THC was inferior to high-dose metoclopramide in one study. There are no comparisons of THC to the modern serotonin antagonists. Some recent investigations have shown that THC in low doses improves the efficacy of other antiemetic drugs if given together. There is evidence from clinical studies that cannabinoids also effective in nausea and vomiting due to radiotherapy and after surgery. In folk medicine cannabinoids are popular and are often used in other causes of nausea including AIDS, hepatitis and nausea in pregnancy.

Cannabinoids as antioxidants and neuro-protectants

Neuropathic pain





Several surveys showed that relief from chronic pain is the most common condition mentioned by patients who use medical cannabis. A large number of clinical studies have shown the analgesic properties of cannabis products. Among possible indications are neuropathic pain due to multiple sclerosis, damage of the brachial plexus and HIV infection, pain in rheumatoid arthritis, cancer pain, headache, menstrual pain, chronic bowel inflammation and neuralgias. The combination with opioids is possible, and some studies indicate moreover that the use of cannabinoid medicines may lead to a reduction in opioids consumption.

Parkinson’s Disease

Post Traumatic Stress Disorder


Prenatal exposure


According to small clinical studies cannabinoids taken internally or externally as ointment ameliorate pruritus by different causes, for example, severe pruritus in the course of liver diseases.

Sleeping disorder

According to a few studies and case reports, cannabis or cannabinoid medicines may alleviate sleeping disturbance, specifically among patients with obstructive sleep apnea, fibromyalgia, chronic pain, or multiple sclerosis.

Schizophrenia / Mental disorders

An improvement of mood in reactive depression has been observed in several clinical studies with THC. There are additional case reports claiming the benefit of cannabinoids in other psychiatric symptoms and diseases, such as sleep disorders, bipolar disorders, schizophrenic psychosis, and dysthymia. According to some case reports THC was effective in otherwise treatment-refractory heavy compulsive disorders. In addition, studies and case reports also suggest that cannabinoids may be beneficial for improvement of anxiety symptoms. Cannabinoids may also reduce symptoms of posttraumatic stress disorders, such as nightmares, global clinical state, and general well-being. Various authors have expressed different viewpoints concerning psychiatric syndromes and cannabis. While some emphasize the problems caused by cannabis, others promote the therapeutic possibilities. Quite possibly cannabis products may be either beneficial or harmful, depending on the particular case.

Sickle Cell Disease

Sleep modulation


Spinal Cord Injury


Tea as medicine

Tobacco vs Cannabis

Tourette’s Syndrome

There are some positive anecdotal reports of therapeutic response to cannabis in Tourette’s syndrome, dystonia and tardive dyskinesia. The use in Tourette’s syndrome is currently being investigated in clinical studies. Many patients achieve a modest improvement, however some show a considerable response or even complete symptom control. In some MS patients, benefits on ataxia and reduction of tremor have been observed following the administration of THC. Additionally, cannabis products may prove useful in levodopa-induced dyskinesia in Parkinson disease without worsening the primary symptoms.

A small study showed that inhaled cannabis improved the motor symptoms of patients with Parkinson’s disease, including tremor, rigidity and bradykinesia. Despite limited evidence regarding effectiveness for treating patients with Huntington disease, the American Academy of Neurology guideline concluded that “nabilone (a synthetic derivative of THC) possibly modestly improves Huntington’s disease chorea.” Anecdotal reports of patients with Amyotrophic Lateral Sclerosis (ALS) suggest that cannabis may provide symptomatic benefits to such patients. Similarly, patients’ reports point to the potential of cannabis in alleviating symptoms associated with Dystonia.


Wilson’s Disease


Miscellaneous, Mixed Syndromes

There are a number of positive patient reports on medical conditions that cannot be easily assigned to the above categories, such as hiccup, high blood pressure, tinnitus, chronic fatigue syndrome, restless leg syndrome, and others. Several hundred possible indications for cannabis and THC have been described by different authors. One example is the successful treatment of a chronic hiccup that developed after a surgery. No medication was effective, but smoking of a cannabis cigarette completely abolished the symptoms.

Cannabis products often show very good effects in diseases with multiple symptoms that encompassed within the spectrum of THC effects, for example, in painful conditions that have an inflammatory origin (e.g., arthritis), or are accompanied by increased muscle tone (e.g., menstrual cramps, spinal cord injury), or in diseases with nausea and anorexia accompanied by pain, anxiety and depression, respectively (e.g. AIDS, cancer, hepatitis C). This is also the case for elderly patients, who often suffer from multiple symptoms and comorbidities.

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