According to a recent study, around one third of people in the U.K who developed coronavirus (COVID-19), went on to experience long term symptoms often referred to as “Long COVID”. Experts believe that more than two million people could have been affected in this way. Findings from the React-2 (Real-time Assessment of Community Transmission) study from Imperial College London used self-reported data from 508 707 adults aged 18 or older who took part in three rounds of surveys that were carried out between September 2020 and February 2021, in which they were asked about 29 different symptoms.
Almost one third of people (30.5%) with at least one symptom lasting 12 weeks or more reported having had severe COVID-19 symptoms that had a “significant effect on my daily life” at the time of their illness (Whitaker, 2021).
The term ‘Long COVID’ is used to describe signs and symptoms that last for longer than four weeks after getting COVID-19. According to the British Lung Foundation, there are two stages to Long COVID:
As well as breathlessness and extreme tiredness (fatigue), other common Long COVID symptoms include insomnia, brain fog, joint pain, chest pain, depression and anxiety, generalised pain and muscle aches throughout the body.
As a proportion of the U.K population, the ONS report showed that the prevalence of self-reported Long COVID was greatest in people aged 35 to 69 years, females, those living in the most deprived areas, those working in health or social care, and those with another activity-limiting health condition or disability; prevalence was lowest in people of Asian ethnic background (ONS UK, 2021).
Medical professionals are still assessing the effects and best treatments for those with Long COVID symptoms, and the general recommendation is that they get adequate sleep and exercise only as much as their body would allow.
Whilst researchers continue to focus their efforts into new ways of combating COVID-19, a number of researchers are looking into whether cannabis or cannabis derived CBD (cannabidiol) or THC (tetrahydrocannabinol) might offer support for those suffering from severe forms of this infection. Cannabis has long been known for its therapeutic effects, from chronic pain relief to lowering stress and anxiety, and helping to overcome insomnia (Webb, 2014). But what is the effect of medical cannabis on Long COVID? And how does it work?
Interestingly, there are a number of different ways that researchers think CBD might be able to help in the fight against COVID. One of these its ability to reduce expression of ACE2, an enzyme which is a cellular entry receptor for the virus (Aging, 2020). The main target for COVID, the virus finds the ACE2 protein on a cell’s surface and binds to it to gain entry before replicating itself. A study was carried out by a team at the University of Lethbridge in Canada that analysed the effects of cannabis extracts on ACE2 expression in inflammation-simulated EpiAirway tissues (human-derived cell cultures of differentiated airway epithelial cells) and identified 13 high-CBD C. sativa extracts that decreased ACE2 protein levels, and a number of C. sativa extracts which downregulate (lower the activity levels of) serine protease TMPRSS2, another critical protein required for COVID-19 entry into host cells (Wang, 2020).
Another reason why CBD could help treat Long COVID is due to its anti-inflammatory properties, and the way in which it can help those suffering from the severe lung inflammation that occurs in more serious cases of COVID. Cannabinoids are a group of compounds that mediate their effects through cannabinoid receptors, and include CB1 and CB2. Both of these receptors have been found on immune cells suggesting that they play a key role in regulating the immune system (Nagarkatti, 2009).
A recent study by researchers at Augusta University in Georgia found that CBD may impact Acute Respiratory Distress Syndrome (ARDS), a symptom in some COVID cases which is caused by an overactive inflammatory response- also known as a ‘cytokine storm’.
Inflammation is the process during which our body attacks and neutralises pathogens such as viruses and bacteria. When a foreign pathogen is detected in the body, it sends cells called macrophages to destroy it. Macrophages belong to a group of white blood cells called leukocytes, can also present antigens to T-cells (white blood cells that are key for immunity) and start an inflammatory response by releasing molecules known as cytokines.
However, during severe cases of COVID, the immune system can overreact and release too many of these pro-inflammatory cytokines which can cause the white blood cells to start fighting the healthy cells of the body, instead of the virus. The more that these healthy cells are attacked, the more cytokines are released, leading to a cytokine storm. This inflammation makes it harder for the lungs to remove carbon dioxide, and to pump oxygen around the body, making it a struggle for the patient to breathe.
The Augusta University researchers tested the efficacy of CBD use on cytokine storms by inducing ARDS in mice by giving them a treatment called Poly(I:C). This created a cytokine storm and also caused damage to the lungs of the mice subjects. They then administered CBD therapy which downregulated pro-inflammatory cytokines, and totally or partially reversed the ARDS symptoms. The lung structure of the mice subjects also improved.
A later study by the same team examined the mechanisms behind these earlier results and found that CBD normalises levels of apelin, a peptide known to reduce inflammation, decrease the physical lung damage associated with ARDS and can improve oxygen levels. During a COVID infection, levels of the apelin peptide are low. The mice in the study exhibited a level close to zero. After administering CBD therapy, the levels of apelin expression increased by 20 times and the mice began to recover (Salles, 2020).
Previous, pre-COVID research provides further evidence that CBD can reduce lung inflammation. An animal study carried out in 2018 showed that CBD was able to reduce the production of pro-inflammatory cytokine production and reduce airway inflammation. In this same study, CBD was also shown to reduce pulmonary fibrosis, a condition during which the lung tissue becomes damaged (Vuolo, 2018).
CBD has also been studied as an agent for antiviral activity as it can induce apoptosis (cell death) in mammalian cells, thought to be an essential component of host responses to viral infections and an interesting area for COVID research. Three pre-clinical studies have examined a possible role for CBD as an antiviral agent. One study demonstrated a direct antiviral effect against hepatitis C virus, another investigation showed an indirect viral action of CBD against Kaposi’s sarcoma-associated herpesvirus, and the third study illustrated that CBD mitigated effects of neuro-inflammation induced by Theiler’s murine encephalomyelitis (Hill, 2020).
COVID-19 and associated research remains in its infancy but recent studies strongly suggest a role for CBD by reducing the cytokine storm and inflammation, protecting pulmonary tissues, and re-establishing inflammatory homeostasis. They show that CBD has the potential not only to act as an antiviral agent at early stages of infection but also to protect the host against an overactive immune system later down the line.
Cannabis Access Clinic is an online U.K medical cannabis service available nationwide, led by specialist doctors in the field of pain management. Whilst we have a medical cannabis clinic in London’s prestigious Harley Street, online consultations are also available. Following a referral from your GP or specialist to confirm that you are eligible, we will book you in for a doctor consultation to assess your suitability and if so, provide your prescription. All of our medical cannabis U.K patients that are prescribed medical cannabis are enrolled into research studies and monitored by one of our experienced multidisciplinary team members on a regular basis.
Symptoms of Long COVID, such as muscle aches and headaches mean that pain relief would be welcome by many that suffer from it. Medical cannabis has been shown to be a pain reliever due to its ability to increase serotonin’s effects, a neurotransmitter that can induce pain relief (Baron, 2018).
It can also be a particularly anxious time when you feel isolated from family and friends, and unable to socialise. CBD compounds within cannabis are shown to reduce stress and anxiety. CBD can increase serotonin activity and lower cortisol levels, which helps greatly with stress and anxiety management (Linge, 2016).
Not just a treatment for Long COVID, we prescribe medical cannabis to support those with long term chronic pain, muscle-stiffness caused by multiple sclerosis, severe epilepsy, patients under palliative care, those undergoing chemotherapy, anxiety, insomnia, ADHD and much more.
If you would like to learn more about how our U.K medical cannabis clinics can help you and to find out whether you are eligible for this treatment, please contact us on 020 3322 4688. You’ll find our flagship medical cannabis clinic in London, but our services are available across the country.
See what our patients have to say about the use of Medical Cannabis to relieve Long COVID symptoms:
Ms G Wood
“Having contracted COVID In January this year, I had been suffering from joint pain and chest tightness since. Having tried different medications and seeing no difference I was recommended to try Medical Cannabis at Cannabis Access Clinics. It has been over two months and it is the first time that I feel like myself again, I can’t thank you enough.”
Mrs N Ryan
“I have had most of the Long COVID symptoms and I have seen such a difference since taking your Medical Cannabis oil. I can finally sleep and my daily nausea has stopped.”
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Available online at: https://www.blf.org.uk/support-for-you/long-covid/what-is-long-covid
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Available online at: Link
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