Two Types of Pain & The
Potential Effects of CBD
While pain can be described according to its qualities, such as sharp or dull, hot or cold, tingling, numb, etc. for treatment purposes pain is often divided into two categories, according to its cause:
1. Inflammatory Pain
Inflammation is a function of the immune
system and is your body’s initial response to irritation or damage to the
body’s tissues — like when the area around a scratch turns red and puffy.
The inflammatory process may occur in
response to infection or physical injury (bumps, bruises, fractures) as well as
to metabolic, degenerative, and autoimmune conditions.
When you suffer an acute injury, such as
an ankle sprain, the inflammation is quite noticeable. But when inflammation
occurs internally at lower levels in chronic conditions like irritable bowel
syndrome, heart disease, or diabetes the signs can go unnoticed — potentially
leading to substantial tissue damage.
are two types of inflammatory pain: A) Acute Inflammatory Pain
Acute inflammation is the first stage of
inflammation. It comes on fast and ideally should go away quickly once the
tissue is repaired. Inflammation lasting less than three weeks is considered
This type of inflammatory pain involves
swelling, inflammation, and migration of white blood cells into the affected
During this phase, pro-inflammatory
molecules called cytokines are released, triggering a cascade of responses that
result in swelling, redness, and heat in the injured area.
same cytokines also activate pain receptors, which send pain signals to your
brain. B) Chronic Inflammatory Pain
This form of pain sets in when
inflammation doesn’t resolve after a few weeks’ time. When this happens pain
sensors often become hyper-reactive, leading to a heightened sensitivity to
lower levels of pain —
meaning the pain
signal is triggered much sooner than it would normally.
Chronic inflammatory pain can result from
autoimmune conditions, cardiovascular disease, type 2 diabetes,
gastrointestinal disorders, and others [
Stopping chronic inflammation is an important step in alleviating chronic pain and a major target in pharmaceutical drug development. CBD has been shown to directly increase levels of anti-inflammatory cytokines (messenger molecules) and decrease levels of pro-inflammatory cytokines — thereby reducing inflammation .
2. Neuropathic pain
This type of pain arises when there’s
damage to peripheral nerves, i.e. nerves outside of the spinal cord and brain.
Peripheral nerve damage can result in persistent impairment of nerve function
even after the nerve recovers from the original injury [
for nerve damage may include:
Trauma or injury Exposure to neurotoxic substances Metabolic disorder (such as diabetes or cardiovascular disease) Autoimmune disease (such as rheumatoid arthritis).
Similar to chronic inflammatory pain,
neuropathic pain can cause hypersensitization to pain signals .
However, while chronic inflammatory pain
usually responds well to anti-inflammatory medications, neuropathic pain does
not. Instead, opiate-type drugs (Oxycontin, morphine), anticonvulsants,
anesthetics, and antidepressants are often used to manage neuropathic pain [
drugs may have significant side effects that can be intolerable for some
Dizziness Drowsiness Impaired coordination Impaired vision Loss of memory Impaired speaking ability Increased susceptibility to viral
infections [ 4, 18]. How CBD May Help With
The endocannabinoid system controls the
transmission of nerve pain at many different places along the pain pathway.
Reducing Pain Transmission
Control occurs at the sensory nerves
responsible for transmitting the first pain signals from the damaged tissue, as
well as areas within the central nervous system that control the amount of pain
that reaches the brain [
One of the ways CBD and other
cannabinoids reduce pain transmission is by activating glycine receptors in the
spinal cord — which has inhibitory effects on pain messages [
If less pain signals reach the brain, we
experience less pain.
Protecting Nerve Tissue From Damage
CBD also offers protective effects on the
nerves, which may prevent or reduce nerve damage. This has been shown in
research looking at the protective effects of CBD on chemotherapy-induced nerve
Additionally, the anti-inflammatory
effects of CBD may prevent inflammatory conditions from causing nerve damage —
again, leading to less neuropathic pain [
Supporting Microglia in the Spinal Cord
CBD inhibits the activity of cells in the
brain and spinal cord called
These immune system-derived cells are
tasked with the job of protecting and supporting nerve cells and are known to
accumulate in neuropathic pain syndromes. By inhibiting microglia CBD may
prevent the neuropathic pain response from escalating [
Unlike some conventional pain medications, CBD doesn’t cause drug tolerance, a process in which the same dose becomes less effective over time, prompting the user to take progressively higher doses [
Pain and Your Brain – How Pain
is Amplified by the Central Nervous System
When pain persists and becomes chronic
the interpretive mechanisms in your brain can go awry — leading to
hypersensitization, amplification of pain messages, and worsening of chronic
pain symptoms [
to as [ maladaptive pathological changes
this process can cause physical changes in your brain, evidence of which has
been demonstrated on neuroimaging studies showing reduced connectivity between
areas of the brain and spinal cord where pain messages are processed .
essentially means the more pain you feel, the easier it is to feel pain again,
i.e., the threshold is lowered, so small triggers can lead to inappropriate
Impaired nervous system communication
reduces your body’s ability to interpret and respond to pain appropriately,
resulting in increased activity of the inflammatory cascade. This shows up on
laboratory tests as elevated levels of pro-inflammatory signaling molecules and
decreased levels of pain-inhibiting molecules like IL-10 .
These changes are most evident in
neuropathic pain syndromes but have also been found to occur in chronic
inflammatory conditions. In these types of conditions, pain can persist even
after inflammation has been brought under control .
Pain and Your Emotional State:
How Anxiety & Depression Cause & Compound Chronic Pain
anxiety, and depression are intricately intertwined — they often occur
While it’s easy to see how chronic
inflammatory or neuropathic pain can lead to anxiety and depression, the
reverse can also occur. These negative emotional states can cause physiological
changes in the brain and body that promote pain.
This makes managing pain much more
complicated because now there’s also an emotional aspect to consider.
Anxiety & Pain: Fanning the
Chronic pain sufferers often become
anxious about their condition. Once anxiety sets in it activates the stress
response resulting in elevated levels of stress chemicals — notably cortisol
and pro-inflammatory cytokines.
Studies show these stress chemicals may
cause pain-processing areas of the brain and spinal cord to become
hypersensitive to pain messages — a condition known as anxiety-induced
essentially means when we’re stressed we experience more inflammation and feel
more pain. Depression & Pain: A
The relationship between depression and
chronic pain may be mutually reinforcing.
Chronic pain can cause depression by
inhibiting secretion of dopamine [
a neurotransmitter responsible for feelings of reward and accomplishment — such
as when you perform well in school or at work, or successfully complete a
marathon (or a 5K).
Conversely, depression, i.e. low dopamine, has
been found to suppress activity in certain areas of the brain that inhibit pain
messages, resulting in heightened pain perception [
To boil it down, pain causes depression by lowering dopamine levels — and low dopamine causes pain by suppressing areas of the brain responsible for controlling pain.
How CBD May Help With Anxiety
There’s promising evidence that CBD offers
benefits for treating complex pain syndromes involving anxiety and depression.
A large clinical study of psychiatric patients
with anxiety and sleep disorders found that anxiety decreased and sleep quality
improved significantly within the first month of CBD supplementation [
CBD has also been shown to decrease symptoms
of depression in laboratory animal studies [
However, there’s still much to learn about the
complex cause-effect relationship between pain, anxiety, and depression and CBD
may prove helpful for some people, in this regard, but less so for others.
CBD & Pain Relief: Benefits
at All Levels of the Pain Response
CBD may work through mechanisms that
address the pain response at all levels of the peripheral and central nervous
systems. Through these effects, CBD may provide relief for acute and chronic
inflammatory and neuropathic pain .
1. CBD at The Site of Injury
CBD has demonstrated potent
anti-inflammatory effects, which in
preclinical studies have been found to inhibit pain and prevent further tissue
In autoimmune conditions, such as
rheumatoid arthritis, type 1 diabetes, and others, inflammation and related
tissue destruction occurs on a continual basis and is one of the underlying
causes of pain.
CBD’s anti-inflammatory activity may play
a key role in pain management in these cases as well as in degenerative
metabolic and neurological conditions such as type 2 diabetes, atherosclerosis,
and Alzheimer’s disease, where inflammation also plays a key role [
The endocannabinoid system also plays an
important role in maintaining balance in the gastrointestinal system. CBD may
prove helpful in managing chronic gastrointestinal pain syndromes, such
as Crohn’s disease, irritable bowel syndrome, and ulcerative colitis .
2. CBD in the Spinal Cord on the
Way to the Brain
CBD shows promise in early studies for
its ability to affect pain messages at the
cord level. It interacts with receptors for glycine — a calming
neurotransmitter that modulates the transmission of pain in the brain and
spinal cord .
This may indicate a potential role for CBD in preventing or managing chronic pain conditions without causing the sedative effects that typically occur with other pain medications.
3. CBD in the Brain
Endocannabinoid receptors (CB1 and CB2
receptors) work in the brain where pain messages are interpreted. Activation of
CB2 receptors in particular help promote the release of
dopamine — which has pain-inhibiting activity .
There’s evidence that CBD works in areas
of the brain where memories are stored to suppress harmful or fearful memories
that trigger anxiety [
29]. This could prevent the stress response to
certain memories in conditions like PTSD that contribute to the overall pain
CBD may alleviate pain by increasing the
serotonin — one of the
body’s calming neurotransmitters [ 8].
There’s some evidence serotonin may have anti-inflammatory and antioxidant
effects that help modulate pain as well . Drugs that increase serotonin
activity, known as serotonin reuptake inhibitors (SSRIs) are widely used to
alleviate depression and anxiety and are also often prescribed for the
management of chronic pain [ 9].
However, SSRIs are fraught with
Blurred vision Digestive system disturbances Insomnia Sexual dysfunction Weight gain
Preliminary evidence also shows that CBD
may affect inflammatory conditions by increasing the activity of adenosine — a
neuromodulator in the brain that “turns down” inflammation triggered by
hyperactivity in the immune system .
4. CBD in the Gastrointestinal Tract
The endocannabinoid system plays an
important role in maintaining balance in the gastrointestinal system. CBD may
prove helpful in managing chronic gastrointestinal pain syndromes, such
as Crohn’s disease, irritable bowel syndrome, and ulcerative colitis .
What the Studies Show: CBD for
Specific Pain Conditions
Human clinical trials are the gold standard for all medical therapies. However, most human research on cannabinoids largely centers on formulations that include higher levels of THC, often at a
1:1 ratio with CBD. That said, CBD research is rapidly catching up to where it needs to be with regard to the uses and benefits for symptoms like pain and inflammation.
The following human clinical trials and
promising animal studies showcase some of the proven benefits and promising
potential of CBD for specific conditions:
1. Chemotherapy-Induced Pain
An animal study found CBD may prevent
painful hypersensitization of nerve receptors to temperature and pressure, a
side-effect from chemotherapy medications [
The study found that CBD alleviated pain by binding directly to serotonin
receptors in the brain. 2. NSAID-Induced Chronic Pain
NSAIDs are a common class of
anti-inflammatories like aspirin and ibuprofen.
Many kidney transplant patients
experience chronic pain due to toxic effects to the kidneys of NSAID — which they need to take following
In a small clinical trial, kidney
transplant patients were given doses of 50 mg to 150 mg of CBD twice per day.
Results showed partial to complete pain relief in the majority of participants
within the first 15 days of the 3-week study [
3. Neuropathic Pain
A small clinical trial of patients with
neuropathic pain of various origins compared the effects of a sublingual spray
of THC, CBD, or a 1:1 combination of both, for 12 weeks [
Though results showed that THC and THC:CBD combination therapies were more
effective than CBD at reducing pain, CBD produced fewer side effects — such as
drowsiness and dry mouth, while providing modest relief.
The CBD used in the study was not a full
spectrum extract so did not offer the synergistic benefits of the
effect — whereby the presence of other ingredients in hemp (such as
THC and other cannabinoids) make the overall effects stronger.
As a result, when using purified CBD
isolate higher doses might be needed to achieve comparable effects than were
used in this study.
4.Pediatric Muscle & Joint Pain
Children with painful congenital movement disorders were given either CBD oil, a 20:1 combination of CBD with THC, or a 6:1 combination of CBD with THC for 5 months in a clinical trial. Results showed significant improvements in pain severity and a decrease in pain frequency and duration in all 3 groups .
In the 20:1 group, a questionnaire that
measured the overall quality of life, including pain levels, showed improved
scores on an average dose of 92 mg per day of CBD .
A challenging condition to treat, fibromyalgia involves chronic muscle and joint pain throughout the body, along with fatigue, sleep disturbances, and cognitive impairment. In a clinical trial, participants were given one of three forms of medical cannabis, one of which contained a high CBD:THC ratio of nearly 20:1 [
showed that none of the cannabis strains resulted in pain relief that was
greater than placebo. However, a closer look at the
study raises some questions about the effectiveness of its design.
In this study, participants were given
vaporized cannabis in four treatment sessions spaced at least two weeks apart.
Since inhaled cannabinoids are rapidly absorbed but also rapidly cleared from
the bloodstream, the inhalation method produces high peak levels but lower
overall bioavailability compared to other delivery forms.
So, could a different delivery form or a more
frequent dosing schedule that would raise and maintain blood and tissue levels
of CBD produce different results for fibromyalgia patients? Possibly, but more
research is needed to explore this effect.
Best Forms & Dosages of CBD
for Pain Relief
Dosage recommendations for CBD vary
widely. There are many factors to consider when determining the best dose,
The condition being treated The severity of symptoms Individual response to CBD The form of CBD used (capsules,
sprays, vaporizer, etc) The presence of other drugs or
medications Underlying medical conditions The weight and size of the person
taking CBD The age and gender of the person
In animal studies, doses can range from 1
to 20 mg/kg body weight. In studies on seizure disorders in children doses
reportedly range from 0.5 to 300 mg/kg body weight per day [
is a very large dosage range.
In order to determine the best dosage
level for your pain relief needs while avoiding uncomfortable side-effects,
it’s best to take a cautionary approach when dosing with CBD and gradually
increase over a period of two or more weeks .
diary can help you keep track of how well you respond to a particular
product or dosage level. 1. Oral CBD
Oral delivery forms include
oils, capsules, and edibles.
CBD incorporated into foods and beverages
enter the system more slowly and stay in circulation longer than other forms.
Oral CBD is often recommended as a
primary delivery method for managing chronic pain conditions but is poorly
absorbed compared to other methods [
To improve the oral bioavailability of CBD
nanotechnology is being used to convert the highly fat-soluble CBD molecules,
which are difficult to absorb, into tiny nano-particles that are more easily
absorbed in the intestinal tract .
2. Vaporized CBD
Faster acting methods, such as
vape oils and vape
pens are useful for sudden or recent onset of pain or flare-ups of
chronic pain. However, vaporization can be counterproductive for pain
management in some instances in that it can irritate the lungs and increase
inflammation in the body. 3. Topical CBD
Opinions vary with regard to
CBD products. Topical CBD includes salves, ointments, and patches.
Some experts say the best use of topicals is for spot treatment on a
muscle or joint injuries, such as a sprained ankle or pulled hamstring .
Others assert that topical CBD, which is
slowly absorbed into the bloodstream, can be used as a systemic delivery form.
These experts predict that topical CBD may prove particularly effective for
maintaining consistent blood levels of CBD in chronic pain patients,
particularly for those who are unable to tolerate oral CBD or other delivery
forms because of digestive or other issues [
16]. 4. CBD Suppositories
CBD suppositories provide yet another option for patients for whom oral consumption is not recommended, such as those with gastrointestinal conditions who may have difficulty absorbing oral CBD, or for very young or elderly patients .
Summing it All Up: Using CBD For
Pain is a complex process that involves finely
coordinated communication between the body and the brain. Pain sensors are
first activated in response to a trigger, like damage to the tissue, and send
messages which travel to the brain and spinal cord.
Once in the brain, pain signals are
interpreted, causing us to
we think of as pain.
From what we know about pain mechanisms and
the endocannabinoid system’s role in pain management CBD may play a
To sum it up briefly:
CBD acts on
the endocannabinoid system, which functions primarily to maintain
homeostasis or balance, within the body, including acting as one of the
body’s inherent pain management systems. CBD acts at
numerous levels within the pain processing pathways, from the tissue level
where pain is generated to the spinal cord and brain, where pain is
interpreted and managed. Studies show
that CBD may offer considerable pain-relieving benefits for a wide variety
of pain syndromes. Dosing with
CBD for pain is highly individual. It is recommended to start low and
slowly increase dosage levels to find the optimal dose for your particular
Although more research is needed to confirm
the effects of CBD for different types of pain, the research thus far is very
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