Cannabidiol (CBD) oil is made by the dilution of CBD extracts with several carrier oils.
CBD is a cannabinoid derived from the hemp plant (Cannabis sativa) and can mediate neurotransmitter activity by binding to specific receptors of the endocannabinoid system (ECS).
CBD is not psychoactive and has been proven to relieve pain, inflammation, and stress. Hence, it is increasingly becoming popular as an alternative medicine.
Table of Contents
- Chemotherapy Side Effects
- Benefits of CBD against Chemotherapy Side Effects
Chemotherapy Side Effects
Chemotherapy is one of the most popular cancer therapies that involve the use of specific chemicals to halt the progress of the disease.
However, it has several damaging side effects as the drugs often interact with normal body cells and tissues.
The normal cells most likely to be affected by chemotherapy include bone marrow cells, hair follicles, and cells lining the mouth, the digestive tract, and the reproductive system.
Benefits of CBD against Chemotherapy Side Effects
The major benefits of using CBD to treat the side effects of chemotherapy are linked with its nature as a phytocannabinoid that can stimulate the receptors of the endocannabinoid system (ECS). It reduces cisplatin-induced nephrotoxicity and restores normal kidney function. It suppresses the sensation of nausea and vomiting.
CBD also treats severe neuropathic pain that is associated with the administration of the drug, paclitaxel. It also has an anti-inflammatory effect and reduces fluid retention and oedema linked with chemotherapy. CBD also reduces the development of mood disorders in cancer patients.
1. CBD Reduces Cisplatin-Induced Nephrotoxicity
Nephrotoxicity is caused by the presence of toxins in the renal tissue.
It is typically the harmful side-effect of substances like toxic chemicals and even, prescription drugs present in the body.
These toxins adversely affect the kidney function as there are some chemotherapy drugs which alter the standard functioning of the kidneys in more than one way.
The antineoplastic drug, cisplatin, is commonly used in the treatment of numerous solid-organ cancers, such as those of the head, neck, lung, breast, ovary, and testis.
In excess, however, cisplatin is toxic and can cause ototoxicity, gastrotoxicity, and allergic reactions. But the main dose-dependent side effect of cisplatin is nephrotoxicity.
Cisplatin nephrotoxicity can manifest itself in a variety of ways. However, the most severe and one of the more common exhibitions is acute kidney injury (AKI) which generally occurs in almost 20–30% of patients.
Nephrotoxicity rises with the dose and the frequency of administration as well as on cumulative dose of cisplatin, which is common in chemotherapy routines.
Elevated plasma levels of free platinum have been associated with nephrotoxicity, and one study has further implicated that the glomerular filtration rate, as well as plasma magnesium concentrations, declined after cisplatin doses became higher than 50 mg/m2 body surface area but remained constant if the dose was below 20 mg/m2.
Extensive research has been conducted to counteract the renal complications that follow chemotherapy.
A 2009 study by the Zhejiang University has explained that the phytocannabinoid CBD helps in reducing cisplatin-induced nephrotoxicity.
It does so by stimulating a series of anti-inflammatory reactions via the endocannabinoid system (ECS) thereby weakening the inflammation and oxidative renal injury caused by cisplatin.
The anti-inflammatory nature of CBD helps in reducing nephrotoxicity which is one of the major side effects of the chemotherapy drug, cisplatin.
2. CBD Reduces Nausea and Vomiting
Nausea and vomiting are the common symptoms produced due to a triggered emetic reflex.
Several internal and external factors can stimulate the emetic reflex. Most incidents of acute vomiting have a palpable triggering factor (e. g, infection, viral illness, food poisoning, or side effects of drugs) and require the removal of the underlying cause.
Chemotherapy-induced nausea and vomiting (CINV) is one of the most widespread side effects of antineoplastic drugs and can often have a debilitating effect on the cancer patient. Emesis (vomiting) is a defence mechanism stimulated by several inputs.
The chemoreceptor trigger zone of the brain contains dopamine D2 receptors, serotonin 5-HT3 receptors, and opioid receptors.
Irritation of the gastrointestinal mucosa by chemotherapeutic drugs activates the 5-HT3 receptors of the vagal and enteric nervous system inputs.
This results in an increase of serotonin and its metabolites in the bloodstream. The presence of such substances in the blood stimulates the 5-HT3 receptors in the chemoreceptor trigger zone.
Substance P, a neuropeptide, is then released which activates the NK1 receptors to cause vomiting.
The tendency to develop CINV depends upon the type of drug therapy administered to the patient.
Examples of some severely emetogenic drugs include cisplatin, cyclophosphamide, dacarbazine, and carmustine.
As a result, new types of antiemetic drugs have been developed and marketed, becoming a standard in chemotherapy routines.
A 2014 review by the University of Calgary has stated that the anti-emetic and the anti-nausea effects exerted by the phytocannabinoid CBD can make chemotherapy regimens more comfortable for cancer patients.
CBD suppresses the sensation of nausea and vomiting usually by indirect activation of the somatodendritic 5-HT1A receptors in the dorsal raphe nucleus of the brain.
CBD helps in treating nausea and vomiting associated with chemotherapy regimens via the activation of the somatodendritic 5-HT1A receptors.
3. CBD Reduces Chemotherapy-Induced Neuropathic Pain
Neuropathic pain is typically caused by any kind of damage or disease that affects the somatosensory nervous system.
It may get manifested as abnormal sensations called dysesthesia or allodynia which refers to pain caused by generally non-painful stimuli.
The pain may be chronic or episodic (paroxysmal) which is similar to a stabbing pain.
Common sensations felt in the case of neuropathic pain include b urning or coldness, numbness, and even itching.
The pain might occur due to disorders of the peripheral nervous system (PNS) or the central nervous system (CNS).
Hence, neuropathic pain is categorized as peripheral neuropathic pain, central neuropathic pain, or mixed neuropathic pain.
Chemotherapy-induced peripheral neuropathy (CIPN) is a common, dose-limited side effect of anticancer drugs such as platinums, epothilones, vinca alkaloids, and bortezomib. CIPN results in deficits in sensory, motor, and even autonomic function.
Sensory complications include mild tingling sensations to unprompted burning pains as well as hypersensitivity to stimuli. These symptoms affect both hands and feet and usually spread into a ‘glove/stocking’ distribution.
It not only prompts dose reduction and even discontinuation of the therapy but also lowers the quality of life of cancer survivors.
Studies behind the aetiology of CIPN has revealed the occurrence of abnormal mitochondrial structures and function in the myelinated axons (nerve fibres).
Drugs like cisplatin inhibit mitochondrial DNA replication whereas bortezomib triggers apoptosis (cell death) by activating the mitochondrial caspases.
Drugs to lower the neuropathic pain are essential to continue chemotherapy. Alternative medicines like CBD have emerged successful in this field.
A 2014 study by Tempe University School of medicine revealed that CBD helped in relieving paclitaxel-induced neuropathic pain without compromising the drug’s ability to combat breast cancer.
CBD helps in lowering chemotherapy-induced neuropathic pain without reducing the efficacy of the cancer treatment routine.
4. CBD Relieves Chemotherapy-Induced Swelling
Oedema denotes a condition where there is an unusual accumulation of fluid beneath the skin as well as in the body cavities.
Such exorbitant fluid retention can lead to severe pain. Clinically, oedema is physically manifested as swelling.
The severe accumulation of interstitial fluid can be due to a number of underlying factors that affect the balance of the fluid homeostasis.
Swelling is usually an outcome of inflammation in the body which leads to the excess secretion of fluid. Internal swelling is often a side effect of medication or a sign of serious injury.
Fluid imbalance due to kidney failure or inflammation in blood vessels due to cardiovascular complications is major factors that contribute to oedema and swelling.
Chemotherapy-induced swelling is another major side effect of cancer medication.
It can occur due to many reasons such as hormonal changes induced by the drugs, excess fluid retention augmented by medication therapies (for e.g. docetaxel), kidney failure due to drug-induced nephrotoxicity.
Cancer itself can trigger the hypersecretion of interstitial fluid and exert an inflammatory effect.
Anti-inflammatory medications should also be prescribed to counter the side effects of chemotherapy.
Recently, cannabis-derived compounds have come to the forefront in relieving oedema and swelling associated with cancer and chemotherapies.
A review by the University of Massachusetts Medical School established the role of CBD in lowering inflammation and associated damage in the body via the receptors of the endocannabinoid system (ECS).
An experimental study by the Università di Milano-Bicocca showed that the anti-inflammatory nature of CBD helped in reducing oedema.
By activating the receptors of the ECS, CBD helps in lowering inflammation and fluid retention which, in turn, helps in relieving chemotherapy-induced swelling.
5. CBD Promotes Mental and Emotional Health
Depression denotes a persistent state of low mood and distaste for activity that affects the individual’s thoughts, behaviour, tendencies, feelings, and overall sense of well-being.
A depressive mood is a normal temporary emotional reaction to life events but is characterized as a mood disorder (dysthymia) when it becomes chronic.
Depression might also be a symptom of an underlying physical disease or a side effect of certain medication therapies and treatments, particularly chemotherapy.
Cancer patients often become victims of depressive mood disorders both due to the severity of the disease as well as because of the effects of several drugs.
The mental and emotional health of patients is often overlooked due to the more severe physical manifestations of the cancers.
However, prolonged periods of radiation and chemotherapy accompanied by surgeries harshly affect the mental well-being of the patients.
There are several stressors that are triggered by a cancer diagnosis which can lead to anxiety disorders.
A study by the King’s College London has also revealed that chemotherapy possibly hinders adult neurogenesis (the process of formation of neurons) that can lead to clinical depression and anxiety.
Therapies to improve the mental health of cancer patients and survivors are on the rise.
Cannabinoids have become popular in the treatment of anxiety and mood disorders due to their anxiolytic effect.
A 2009 study published in the journal CNS & Neurological Disorders – Drug Targets has elicited the role of CBD in treating depressive mood disorders and anxiety.
It states that CBD generates an anti-depressant and anxiolytic effect by activating serotonergic receptors in the endocannabinoid system (ECS).
CBD helps in treating chemotherapy-induced depression and anxiety by mediating the endocannabinoid system.
It is advisable to consult a medical practitioner before consuming medications containing THC. The dosage depends on the mode of delivery as the CBD products can be orally ingested or inhaled by a vaporizer.
There is no particular prescribed dosage for using CBD oil to treat the side effects of chemotherapy as they encompass several conditions.
However, to lower the severity, small doses of 30-40mg should be consumed, initially, and the optimum dose should be decided as per the individual’s tolerance level.
Vaporizers containing CBD oil can be used to relieve neuropathic pain and nausea. 6-8mg (equivalent to 2 puffs) should be inhaled.
The phytocannabinoid, CBD, has very few proven side effects. Daily oral doses of around 500mg can be had for half a year.
A 2011 review revealed that relatively higher doses of around 1500mg can also be tolerated per day for a period of up to 3 months without producing any undesirable complications.
CBD products have varying amounts of the psychotropic agent, tetrahydrocannabinol (THC), which is responsible for the few side effects.
While the amount of THC permitted in medicinal products is quite low, sensitive individuals might still experience some form of cognitive impairment.
CBD inhibits the activity of the liver enzyme, cytochrome p450, which is involved in the metabolism of common drugs. Hence, consuming CBD might reduce the efficacies of these medications.
Medicinal products containing an excess of THC cause confusion, dizziness, disorientation, nausea, vomiting, fatigue, impaired balance, unsteady gait, hallucinations, and paranoia.
The THC is also responsible for tachycardia, a condition wherein the heart rate gets rapidly raised for a short duration. Cannabis products which have slightly high amounts of THC should not be accompanied by alcohol.
Pregnant and lactating women should consult a gynaecologist before consuming CBD-containing medicines.
Caution should also be maintained while administering THC-containing products to children and adolescents as it might affect their CNS differently.
To summarize, it can be said that CBD greatly improves the quality of lives of patients undergoing chemotherapy.
It restores renal function and filtration by reducing cisplatin-induced nephrotoxicity. CBD usage also diminishes the sensation of nausea and vomiting by indirectly activating the 5-HT1A receptors.
CBD usage also reduces chronic neuropathic pain which is a major nuisance in patients being treated by chemotherapy.
Being anti-inflammatory in nature, it reduces oedema and controls fluid retention which is a side effect of several chemotherapeutic medications. Finally, CBD improves mental and emotional health by preventing depression and anxiety.