There are around 20 million people in the United States who suffer from neuropathic pain. The percentage is significantly higher in two segments – 26% of seniors over the age of 65 and 30% of patients who have been diagnosed with diabetes mellitus.
Neuropathic pain is chronic, which means it lasts for more than 12 weeks. Chronic pain can persist for months or even years. The most common treatment for chronic pain are opiates even though research has shown that they are not effective and might even be dangerous.
What is neuropathy?
Neuropathy refers to nerve pain that is caused by nerve damage. It often occurs in the hands or feet and can affect one or more areas of the body.
Each individual has a central nervous system (CNS) composed of the brain and spinal cord. This system works hand in hand with the peripheral nervous system made up of nerves that connect the CNS to the rest of the body.
The CNS is protected by the skull, vertebral column, and blood-brain barrier. The peripheral nervous system has no such protection and can be vulnerable to a wide range of elements such as bacteria, toxins and injury.
Peripheral neuropathy occurs when there is damage, dysfunction or injury to the nerve fibers, sending false signals to pain centers in the central nervous system.
The two most common types of neuropathy are peripheral and diabetic. Peripheral neuropathy is caused by injury while diabetic polyneuropathy is a result of high blood sugar levels damaging the cells over time.
Peripheral neuropathy can also be traced to alcoholism, physical injury to the nerves, HIV infection, hypothyroidism, autoimmune disease, low levels of vitamin B12, vasculitis, chronic liver disease, chronic kidney disease, rheumatoid arthritis, lymphoma, and toxicity from heavy metals or chemotherapy. [R]
One of the most painful sensations a person can experience, neuropathy is characterized by weakness and pain that typically begin in the hands or feet and progress to the rest of the body. Symptoms include tingling and numbness, shooting and burning, and prickly pins and needles.
Very few treatments offer adequate relief for neuropathy. Patients suffering from this chronic condition often rely on pharmaceutical painkillers.
Peripheral neuropathy can lead to poor quality of life. Many patients experience functional, emotional, and cognitive issues resulting in high rates of physical, psychological, and occupational impairment. Despite the abundance of clinical and epidemiologic data, peripheral neuropathy is often undertreated. [R]
Forms of neuropathy
The symptoms and side effects of neuropathy vary depending on which part of the body is affected. There are four main forms of neuropathy:
- Motor neuropathy
- Sensory neuropathy
- Autonomic neuropathy
Motor neuropathy refers to neuropathic pain caused by damage to the nerves that control your movement. This can lead to muscle weakness that might prevent you from lifting things or even carrying your own body weight.
Sensory neuropathy is caused by damage to the nerves that control your senses. This form of neuropathy affects touch, pain, temperature and other sensations. The inability to feel pain in your feet can prevent you from walking properly – a common condition in diabetic patients.
Autonomic neuropathy is a result of damage to the nerves that control important functions such as heartbeat, blood pressure, digestion, sweat and bladder. This is the worst form of neuropathy as it affects involuntary survival processes. If the CNS is unable to tell the heart to beat, the consequence could be lethal.
Mononeuropathy refers to damage to a single nerve outside of the CNS.
Peripheral neuropathy likely involves more than one of these conditions. Here are common signs that you may have neuropathy:
- Numbness in the affected area
- Burning sensation
- Stabbing or shooting pain
- Muscle weakness
- Muscle cramps
- Twitching muscles
- Difficulty standing or walking
- Lack of coordination and loss of balance
- Inability to feel pain in the affected area
These symptoms depend on the type and form of neuropathy you are suffering from.
Traditional treatment for neuropathy
Neuropathy occurs in patients with multiple chronic conditions and is especially difficult to treat. [R]
Doctors often prescribe anti-inflammatory painkillers, anti-seizure medication, tricyclic antidepressants, and serotonin-norepinephrine reuptake inhibitors. Topical treatments and physiotherapy are supposed to reduce symptoms of neuropathy in the feet. Spinal cord stimulation is a more invasive option.
Neuropathic pain is very difficult to treat because it is caused by nerve damage instead of actual injuries. With no specific area to treat, applying topical pain relievers such as ibuprofen gel can be highly ineffective.
These treatments only target the symptoms and not the underlying cause of the condition. They are also expensive and can have considerable adverse effects. Traditional treatment for neuropathy offers pain relief that is not sufficient in improving quality of life for many patients. [R]
Due to the severity of the pain that comes with neuropathy, more people have turned to prescription opioids. Neuropathic pain does not go away easily, and prescribing opioids as pain medication can be dangerous long-term. These medications are so addictive that patients continue to crave for it long after the prescribed period has lapsed. The result? We now have an opioid crisis, with tens of thousands dying each year from overdose.
Neuropathy patients need a sustainable solution that significantly reduces pain and improves quality of life. Can CBD oil do this?
Cannabis for treating neuropathic pain
More than 380 million people are suffering from neuropathy across the globe, and opiates have become the go-to treatment for many of them. Cannabis has been used as an analgesic for treating pain for centuries, and now it is making a comeback in neuropathy thanks to recent research and anecdotal evidence. [R]
Cannabis sativa contains more than 400 chemical compounds. Tetrahydrocannabinol (THC) and cannabidiol (CBD) are the most dominant and the most studied cannabinoids known to have analgesic effects. [R]
As the psychoactive component of cannabis, THC can alter perception, heighten sensations, increase libido, distort time and space, decrease short-term memory, and cause dry mouth, impaired motor function, paranoia, and anxiety.
CBD is the non-psychoactive component of cannabis. It has anti-inflammatory and antioxidant properties that can help reduce pain and inflammation without the mind-altering effects of THC. [R]
In addition to phytocannabinoids, the cannabis plant contains flavonoids, tapenoids, and terpenes which may produce synergistic effects. [R]
Different strains of cannabis contain different amounts of these components, making it difficult to conduct and compare clinical studies.
How CBD can help
Cannabis Sativa has been used as a pain reliever since way back 10,000 years ago. Today modern medicine and technology has made it possible to extract one of its most important analgesic substances – CBD – and suspend it in oil. With CBD now available in oral and topical forms, you do not have to smoke weed (and get high) every time you need pain medication.
Studies have shown that CBD is a powerful anti-inflammatory that is more effective than pharmaceutical drugs in providing pain relief, with none of the addictive side effects.
In 2012, a study published in the Journal of Experimental Medicine revealed how CBD can reduce pain and inflammation. The results indicated that patients were not likely to build up a tolerance to CBD so there is no need to constantly increase dosage. According to the researchers, CBD has the potential to treat chronic pain.
Plant-derived cannabinoids such as CBD and THC bind to human endocannabinoid receptors located throughout the body. These receptors are responsible for regulating several physiological systems including mood, memory, appetite and pain. While pharmaceuticals are also designed to interact with endocannabinoid receptors, they rarely bind as naturally as phytocannabinoids. This is why medical cannabis offers a more effective treatment option for conditions like neuropathy which is difficult to treat. Although pharmaceutical therapies do provide symptom relief, it cannot justify their negative side effects and potential for addiction. CBD works more efficiently without the risk of life-threatening addiction.
Unlike THC, CBD does not produce a euphoric "high" that alters the mind. This is because CBD and THC bind to the receptors in very different ways.
The endogenous cannabinoid system found in mammals plays a role in regulating the development, homeostasis, and neuroplasticity of the central nervous system (CNS). It also modulates pain transmission along the nociceptive pathway.
Two of the most abundant endocannabinoids in the body are anandamide and 2-arachidonylglycerol. The CNS produces these compounds on demand as a reaction to pain. They target the CB1 and CB2 receptors located throughout the central and peripheral nervous systems as well as organs and tissues. [R] [R]
CB1 receptors are found primarily in the CNS, specifically in areas that involve movement (basal ganglia and cerebellum) and memory (hippocampus). CB1 receptors in the brain, the periaqueductal gray, and the dorsal horn of the spinal cord help conduct and modulate pain signals.
CB2 receptors are found primarily in peripheral organs and tissues. They regulate the immune system, particularly involved in splenic, tonsillar, and hematopoietic cells. These receptors control inflammation and pain response (allodynia and hyperalgesia).
When a nerve injury occurs, neurons along the nociceptive pathway trigger a series of cellular events that result in pain-sensitive nerve endings.
Cannabinoids are able to reduce pain by modifying these cellular events and inhibiting nociceptive conduction in the dorsal horn of the spinal cord and in the ascending spinothalamic tract.
As CB1 receptors impede pain conduction, CB2 receptors inhibit the release of nociceptive agents.
In a 2009 study published in Neurotherapeutics, researchers evaluated the effects of cannabis and CBD on patients suffering from neuropathic pain. The findings showed a considerable reduction in pain and significant improvement in quality of life. The researchers explained that CB2 receptors appear to help heal neuropathic pain by restoring damaged nerve cells and promoting re-growth of healthy cells.
While CBD studies are limited to preclinical data, there is evidence that CBD can suppress chronic neuropathic pain and even provide cellular protection after a nerve injury. [R]
Multiple research studies reveal why cannabis is a preferred option in managing neuropathic pain:
- It is more effective even in patients who have not responded to pharmaceutical therapies
- The psychoactive side effects are not as debilitating as the side effects of opiates
- Cannabinoids can treat not just pain and inflammation but also anxiety, sleep deprivation, and mood disorders
- While single cannabinoid therapies are extremely successful, the effects of CBD increase dramatically when it works together with multiple cannabinoids – also called the entourage effect
A study conducted by Dr. Ethan Russo compared the pain relief capabilities of THC and CBD against other forms of cannabis medication. Results showed that the CBD was mostly responsible for providing pain relief – contradicting the common assumption that THC is more effective in masking pain and coping with injuries. CBD not only suppresses pain but improves overall quality of life in patients who are dealing with difficult-to-treat conditions such as neuropathy.
Despite its association with cannabis, CBD poses "no adverse public health risks" and is considered safe by the World Health Organization. Its Global Expert Committee on Drug Dependence even recommended CBD to be classified as a medicine.
Nabiximols (Sativex) is a mouth spray containing THC and CBD. It was approved in the United Kingdom in 2010 as a botanical drug for treating neuropathic pain, spasticity, overactive bladder, and symptoms of multiple sclerosis. It is also approved in Canada and several European countries.
CBD and neuropathy: what the science says
The anecdotal evidence demonstrating the analgesic efficacy of cannabis dates back to 5,000 years ago. Pain relief is a significant and consistent part of cannabis documentation.
Many experts in the medical field acknowledge that cannabis can be a safe and effective therapy option for chronic pain when nothing else works.
Neuropathic pain is one particular medical condition that can be resistant to pharmaceutical drugs. Cannabis has shown to effectively reduce symptoms even when taken in small doses.
There have been a number of studies that evaluated medical cannabis for treating neuropathic pain.
The results of a randomized, crossover clinical trial in 2008 seem to support the efficacy of inhaled cannabis in its flower form when used as monotherapy or adjunctive therapy for the relief of neuropathic pain. Many studies also report secondary benefits, including better sleep and functional improvement.
That same year, a double-blind, placebo-controlled crossover study evaluated the effects of cannabis in 38 patients who were suffering from central or peripheral neuropathic pain. Participants either smoked cannabis or placebo cigarettes – 2 puffs in the first 60 minutes, 3 puffs at 120 minutes, and 4 puffs at 180 minutes. Pain intensity was significantly reduced in the cannabis group compared with placebo.
In 2009, a double-blind, placebo-controlled crossover trial was conducted in HIV-related neuropathy patients who were unresponsive to two or more analgesics. Participants were randomly assigned to smoke cannabis or placebo while continuing their prescription therapy. Among the 34 enrolled patients, 28 completed both cannabis and placebo treatments. The Descriptor Differential Scale of Pain Intensity showed a reduction in pain intensity from baseline at the end of each week. Out of the 28 patients, 46% reported a pain reduction of 3.3 points or 30 percent.
In another randomized crossover clinical trial in 2010, researchers analyzed posttraumatic or postsurgical neuropathic pain in 21 patients. Participants inhaled four different formulations of cannabis throughout four 14-day periods. Patients reported significantly less pain, with average scores decreasing from 6.1 to 5.4 on an 11-point scale. Some also reported improved sleep, better mood, and less pain after smoking cannabis. Common side effects included throat irritation, headache, dizziness, and fatigue. These adverse events increased with higher doses and greater potency.
A 2011 study published in Clinical Pharmacology & Therapeutics found that cannabis may augment the analgesic effects of opiates. Evaluating 21 individuals with chronic pain, the researchers administered regular doses of cannabis along with twice-daily doses of prescribed opioids. On average, participants reported a 27 percent decrease in pain.
In 2013, another double-blind, placebo-controlled crossover study assessed the effect of vaporized cannabis on 39 patients with treatment-resistant central and peripheral neuropathic pain. The primary outcome was a 57% reduction in pain intensity in the low-dose cannabis group and 61% in the medium-dose cannabis group. Psychoactive effects were minimal and reversible.
The European Journal of Pain published the results of a randomized, placebo-controlled parallel-group study in 2014 which evaluated 246 patients with peripheral neuropathy (allodynia). Among the participants, 128 were given a THC-CBD combination oromucosal spray while 118 took placebo. Over the 15-week trial, all participants continued their standard therapies. The cannabis group reported reduced pain and significantly better sleep.
In 2015, a randomized, double-blind, placebo-controlled crossover study evaluated diabetic peripheral neuropathy in 16 patients who each had experienced neuropathic pain in their feet for at least half a year. Participants inhaled different doses of cannabis or placebo. Pain scores were lower with cannabis treatment compared with placebo, with the highest dose producing the greatest analgesic effect.
That same year, researchers conducted a review on five randomized controlled trials in 178 patients across North America. All had experienced neuropathic pain for at least 3 months. In two studies, patients had HIV-related neuropathy. In three studies, patients had neuropathy related to trauma, diabetes, or spinal cord injury. All five trials administered whole cannabis plant therapies provided by the National Institute on Drug Abuse (NIDA). The findings revealed that 1 of every 5 to 6 patients treated with cannabis had experienced at least 30% pain reduction.
There was another review in 2017 of 13 trials conducted on 246 patients with neuropathy. These studies evaluated the effects of different cannabis preparations on central or peripheral neuropathic pain resulting from various conditions. According to the researchers, patients actively treated with cannabis were more likely to report a 30% reduction in neuropathic pain.
In 2018, a Cochrane review analyzed 16 trials conducted on 1,750 adult patients with neuropathic pain. Ten studies administered a THC/CBD oromucosal spray. Two studies used a synthetic cannabinoid mimicking THC (nabilone). Two studies applied vaporized herbal cannabis. Two studies gave plant-derived THC (dronabinol). And one study evaluated an analgesic (dihydrocodeine). The cannabis treatments resulted in 50% or greater pain relief compared to placebo.
Clinical studies have found cannabis to be effective in reducing pain, improving sleep, and increasing function in patients with peripheral neuropathy – even those with symptoms that are resistant to standard therapies. [R]
CBD is an emerging therapeutic option for reducing the impact of inflammation on oxidative stress. [R]
CBD and neuropathy: cannabis vs. opiates
- According to the Centers for Disease Control and Prevention (CDC), the amount of prescription painkillers prescribed and sold in the United States has quadrupled since 1999
- 44 people die from prescription opioid overdose every single day
- The leading cause of injury death in 2013 was drug overdcose
- There were more drug overdose deaths than traffic accident fatalities among adults age 25 to 64
- 3% of drug overdose deaths (16,235 people) involved prescription opioid painkillers
- Prescription opioid abuse resulted in lost productivity, healthcare costs, and criminal justice costs totaling $55.7 billion in 2007 [R]
On September 6, 1988, Drug Enforcement Agency (DEA) Administrative Law Judge Francis L. Young stated the following facts in his ruling "In the Matter of Marijuana Rescheduling Petition" (Docket #86-22). [R]
- Marijuana is far safer than common foods we consume
- The extensive medical literature does not contain any record of a proven, documented cannabis-induced fatality
- There is no credible medical report to suggest that marijuana has caused a single death
- Drugs are assigned an LD-50 rating which indicates the fatal dosage. The LD-50 rating for aspirin is 1:20 which means a person would need to consume 20 times the recommended dosage to induce death. Valium has a rating of 1:10 while some cancer medications are at 1:1.5.
CBD dosage for pain management
CBD dosage is generally based on body weight, type of ailment, and severity of symptoms. Below is a recommended table for daily CBD oil dosing.
Under 25 lbs: 2 mg
25-50 lbs: 4 mg
51-100 lbs: 6-8 mg
101-150 lbs: 8-12 mg
151-230 lbs: 12-15 mg
Over 230 lbs: 15-30 mg
Under 25 lbs: 4 mg
25-50 lbs: 8 mg
51-100 lbs: 9-12 mg
101-150 lbs: 13-15 mg
151-230 lbs: 16-30 mg
Over 230 lbs: 31-50 mg
Under 25 lbs: 6 mg
25-50 lbs: 12 mg
51-100 lbs: 12-15 mg
101-150 lbs: 16-30 mg
151-230 lbs: 31-50 mg
Over 230 lbs: 50+ mg
2.5mg to 20mg of CBD (with or without THC) for 25 days [R]
The ideal dosage for chronic pain is usually between 10mg and 20mg taken in multiple doses throughout the day.
While most people tolerate CBD well, there are possible side effects. According to a review in Cannabis and Cannabinoid Research, these include:
- Change in appetite
- Weight gain or weight loss
At high doses, adverse effects such as difficulty concentrating, lightheadedness, and fatigue may occur.
If you are currently taking any prescription drug, CBD can also affect how your body metabolizes those medications. You should talk to your doctor or healthcare provider before trying CBD so they can monitor any changes and make adjustments accordingly.
Neuropathic pain is serious and can severely affect quality of life. The consequences are not limited to constant and intense pain but depression, mobility issues, and other harmful side effects.
Research has demonstrated how CBD can be an effective suppressant of neuropathic pain through its stimulation of the endocannabinoid system. CBD is by no means a cure but it can help ease the symptoms of your condition. In cases where neuropathic pain is extremely severe, nerve cell damage can be quick and irreparable and all you can do is mitigate the discomfort as best as you can.
Clinical trials suggest that CBD could be a safer and more effective option than opiates. Traditional treatments often offer little relief and can sometimes make matters worse with their addictive side effects. CBD oil has shown great potential in pain relief – not just acute pain but chronic neuropathic pain.
If you suffer from neuropathy and no medication or home remedy seems to work, talk to your doctor today about CBD for pain management.
To know more about CBD and neuropathic pain, check out this 5-part series from Dr. Rosemary Mazanet published by the Foundation for Peripheral Neuropathy.