Pain is a sensation of discomfort experienced upon an encounter with a stimulus that has potential of causing harm to the tissues of our body.
The stimuli may be transient in nature (such as contact with heat or cold) or prolonged (tissue damage due to inflammation, mechanical injury etc).
When there is an encounter with these stimuli, the pain is felt due to the signals sent to the brain through the nervous system. These signals are a way of making the body aware of the damage.
The pain is classified under acute or chronic. The acute pain lasts for a shorter duration (such as until an injury lasts) and the chronic pain lasts for a prolonged period (such as in arthritis).
There are different types of pain based on the mechanism of the action. These are commonly identified as nociceptive pain, neuropathic pain and psychogenic pain.
The nociceptive pain occurs due to activation of pain receptors in the tissues of the body upon damages such as injury to muscles, skin, bone, joint tissues, internal organs etc. This pain is characterized as dull, sharp, aching, burning, prickling, or may sometimes involve inflammation.
The neuropathic pain occurs due to changes in the nervous system induced by a stimulus like trauma, certain diseases or chemotherapy. It also occurs due to heightened response to a pain stimulus. This kind of pain is described as unusual and unfamiliar and may involve tingling, burning or electricity like sensations.
The psychogenic pain is caused by psychological distress and an involvement of an external stimulus does not seem to be there.
Pain is manifested as a symptom of a number of diseases and injurious conditions to a tissue and is a major cause of discomfort. Therefore, it becomes very important to tackle the pain.
The treatment of pain commonly involves the use of pain-killers. Other options like physiotherapy, acupuncture, exercise, stress management, lifestyle changes, surgery etc are also employed depending on the type of pain.
The frequently used pain-killers, i.e. the drugs that relieve the sensation of pain are the NSAIDs, analgesics (ex. Paracetamol), opoids, anticonvulsants, local anesthetics and antidepressants.
However, these drugs pose some serious side-effects like nausea, dizziness, sedation, kidney damage, gastrointestinal problems, addiction and many more. Sometimes there is tolerance to these drugs that reduces their effectiveness.
Keeping in the view of these problems, there is an increased inclination towards natural remedies for the pain management which are not only safe but effective as well.
Such a potential is there in curcumin, a compound of the humble spice turmeric.
What is curcumin?
Curcumin or diferuloylmethane is a polyphenolic compound present in the rhizome of turmeric (Curcuma longa).
This component imparts the turmeric its yellow-orange colour.
It is the most active of all the constituents present in turmeric and has an ability to interact with the biological components and pathways of a cell.
Curcumin’s biological activities have therapeutic potential and been utilized in the treatment of a number of diseases. These activities include antioxidant, anti-inflammatory, antimicrobial, anti-cancer, immune-modulatory, analgesic etc.
How does curcumin relieve pain?
The mechanism of pain involves nociceptors (the sensory receptors present in the nerves). The nociceptors are activated by a noxious (harmful) stimulus. Upon sensing a noxious stimulus, the nociceptors send the signals to the brain which are perceived as pain.
Depending on the type of stimulus, the mechanism of nociception differs. Thermal and chemical stimuli are known to be detected by the TRP (transient receptor potential) proteins. These proteins have a key role in inflammatory pain as well as neuropathic pain.
There is also an involvement of ion voltage channel proteins such as VGSC (voltage gated sodium channels) in the chronic pain pathways. These are cellular mechanism involved in pain.
In case of inflammation related pain, the pro-inflammatory molecules have a central role in the nociception. The pro-inflammatory molecules such as TNF-α, IL-1β, IL-6 etc modulate the neuronal activity to generate the pain.
Curcumin has a potential of modulating the nociceptive pathways to relieve pain. Depending upon the site and type of pain different anti-nociceptive mechanisms are involved.
It exerts anti-nociceptive (reducing sensitivity to pain) by acting on the TRP proteins to desensitize the cells to the pain. Curcumin has ability to modulate ion channel proteins such as VGSC as well, which is helpful against nociception.
The inhibitory action of curcumin against the pro-inflammatory molecule expressions, such as those of TNF-α, IL-1β, IL-6 etc, is also useful in relieving pain.
Additionally, curcumin is known to reduce hypersensitivity to inflammatory pain by reducing the activation of acid-sensing ion channels (ASICs) involved in the nociception.
The involvement of opoid receptors (Delta and Mu receptors) is known in the pain-relief. These receptors are a part of an innate analgesic mechanism of the body. Curcumin also increases the activity of these receptors to induce anti-nociception and thus, pain-relieving effect.
Moreover, many studies have proven the safety and efficacy of curcumin as an analgesic (pain-relieving agent). The effectiveness of the curcumin is also found to be higher than the commonly used analgesic drugs like nimesulide and acetaminophen.
6 Types of Pain And Aches Curcumin Relieves
There are a large number of studies on the pain-relieving action of curcumin in various types of pain whether they fall in the category of nociceptive pain or neuropathic pain.
1.Curcumin relieves inflammatory pain in Arthritis
The pain caused in arthritis is mainly due to the action of pro-inflammatory molecules. The inflammation in the joints increases the sensitivity of nociceptors which is mediated by pro-inflammatory molecules like cytokines, prostaglandins etc.
The anti-inflammatory activity of curcumin comes handy in the treatment of arthritic pain. It inhibits the expression of a number of pro-inflammatory molecules such as, cytokines, prostaglandins, lipoxygenase, cyclooxygenase, metalloproteins and many more.
The anti-inflammatory action has been found to alleviate the pain significantly along with other symptoms in the arthritis patients.
In a knee osteoarthritis model, the inhibition of inflammatory mediators like TNF-α, interleukins and metalloproteins by curcumin exhibited significant pain relief.
It has also been found to reduce the hypersensitivity to pain in arthritis by inhibition of inflammatory mediators and glial cells (involved in nociception) of spinal cord.
What does it mean?
It means use of curcumin can effectively attenuate arthritic pain. Its anti-inflammatory activity targets the nociception induced by the pro-inflammatory molecules.
2.Curcumin relieves stomach cramps
The pain in abdomen is caused by the activation of visceral nociceptors. The stimuli such as inflammation, acidosis (excessive acid in stomach), shortage of glucose etc induce the visceral nociceptor activation and result into the sensation of pain.
Curcumin has been found to be efficacious in relieving the abdominal pain induced by various gastrointestinal disorders.
It is known to produce anti-nociceptive effects through the opoid system in case of acid induced visceral nociception, i.e. abdominal pain.
In the patients with peptic ulcer and irritable bowel syndrome, curcumin administration was able to reduce the abdominal pain significantly.
The gut nociception is alleviated by curcumin through the modulation of TRP proteins as well. Curcumin antagonizes (disaffects) the receptor TRPV1 to inhibit the visceral nociception.
What does it mean?
It means administration of curcumin can attenuate the abdominal pain in various gastrointestinal disorders. It does so through various mechanisms such as, by inducing innate analgesic opoid mechanism and by disaffecting the receptors like TRPV1 (involved in nociception).
3. Curcumin remedies muscle pain
Very often we experience pain and soreness in the muscles of our body after exercising. There are many factors involved in this, such as lactic acid, increased levels of creatine kinase in the blood, pro-inflammatory molecules etc.
Curcumin has been found to decrease the production of inflammatory markers like, IL-6 induced due to exercise. This can have positive implications on the reduction of exercise induced muscle pain.
It can also reduce the pain caused by delayed onset muscle soreness or DOMS (pain and stiffness in muscle caused due to exercise). This was a result of decrease in IL-6 production post-exercise.
In a study with Meriva (a more bioavailable formulation of curcumin), it was observed that there was a significant effect on pain intensity and muscle injury caused by exercising. Curcumin lowered the levels of inflammatory markers in the muscles which in turn led to lowering of the pain and the muscle damage.
What does it mean?
It means curcumin supplementation can be helpful in reducing the pain in muscles of the body caused due to exercise. This is achieved by lowering the production of inflammatory markers in the muscles produced after exercising.
4. It benefits in neuropathic pain
Neuropathic pain is caused as a result of the damaged or dysfunctional neurons. This damage may be triggered by ailments like cancer, diabetes, spinal injury etc resulting into incorrect signalling of pain.
The role of TRP proteins, ion channels and other receptors are there in the nociception.
Various pro-inflammatory molecules are also involved which are expressed as a result of immune response against the nerve injury caused by the diseases. The inflammation mediators that are commonly involved here are TNF-α, BDNF, prostaglandins, IL-1β etc.
The anti-inflammatory activity of curcumin is highly valuable against the neuropathic pain.
Administration of curcumin is found to be helpful in attenuating the chronic neuropathic pain. It is a result of inhibition of cycloxygense-2 (COX-2) enzyme (an inflammatory marker involved in prostaglandin production) by it.
It is known to down-regulate the synthesis of IL-1β in spinal cord, inhibit NAPL-1 inflammasome (involved in nociception) and activates JAK2-STAT3 pathway (involved in maintenance of neuropathic pain). All these actions of curcumin result into reduction of the neuropathic pain.
The anti-nociceptive effect of curcumin is also achieved by the reduction in the BDNF (pro-nociceptive molecule) levels in case of neuropathic pain.
In a study, curcumin treatment was able to prevent the occurrence of neuropathic pain by reversing the damage to the nerves through modulation of certain signalling pathways.
What does it mean?
It means curcumin supplementation can reduce the neuropathic pain by decreasing the expression of various pro-inflammatory and pro-nociceptive molecules. It can also prevent the nerve injury and thus, prevent the occurrence of the pain.
5. It benefits in Hyperalgesia or increased pain sensitivity in disorders like fibromyalgia
Hyperalgesia is the phenomenon of an increased sensitivity to an area where a tissue is damaged by a stimulus. Release of various substances at the area of tissue damage causes sensitization of the nociceptors and results into pain.
Curcumin produces an anti-hyperalgesic effect by antagonizing the TRPV1 receptor (a mediator of hyperalgesia).
Its anti-inflammatory and antioxidant activity is also helpful in attenuating thermal hyperalgesia (caused due to thermal or mechanical stimuli).
The prolonged use of opioid drugs to treat chronic pain can also induce hyperalgesia. Curcumin can ameliorate the opoid induced-hyperalgesia by deactivating the CaMKIIα signalling (involved in nociception).
What does it mean?
It means curcumin can improve the heightened sensitivity in response to noxious stimuli. Thus, it can significantly reduce the nociception and in turn pain.
6. Curcumin remedies post-operative pain and pain due to injuries
Curcumin has been studied for its anti-nociceptive and analgesic effects on a number of other types of pain which we may commonly encounter. In these conditions too, its efficacy has been proven.
Burn injuries are often associated with severe pain. The stimulus, i.e. heat causes hyperalgesia and sensitizes the nociceptors, resulting into the severe pain.
Curcumin, through its anti-inflammatory mechanism not only helps in wound healing but also treats the pain. It has been found to be highly efficacious in reducing the burn pain.
One of the major problems faced after a surgery is severe pain. Most of the surgeries, whether major or minor often result into the occurrence of severe pain. Therefore, the management of postoperative pain is very important.
Curcumin has a potential to alleviate the postoperative pain and thus be useful in the better management of these pain.
It reduces the incision induced inflammation, nociceptive sensitization and brings about the reduction in the postoperative pain.
What does it mean?
It means curcumin is helpful in alleviating pains like those caused by burn injuries or surgery as well. Its anti-nociceptive activity is useful in coping up with the severity of these kinds of pain.
Dosage of Curcumin For Pain Relief
There is no specifically prescribed dosage of curcumin for pain reduction.
A number of studies have employed the curcumin dose in the range of 200 mg to 3000mg in humans.
Depending upon the area of the pain (i.e. tissue), curcumin can be given orally or applied topically.
A large number of curcumin supplements are standardized 95% curcumin with bioperine. The fusion of curcumin with piperine and natural fats improves its abrosrption/ bioavailability in the body. (Read How to improve bioavailability of curcumin?)
The formulations of curcumin that have better bioavailability such as, Meriva and nano-particle delivery systems are being increasingly used.
There are numerous other varieties of curcumin supplements that have an enhanced bioavailability. (Read 8 Popular curcumin supplement types)
Ideally, small dose of curcumin is advisable to start with. The dose should be raised moderately over weeks.
Curcumin consumption is better after meals. Also, its intake should be following at least 3-4 hours of taking a medication.
Safety of turmeric in the diet is renowned. Curcumin has also been established to be safe even in high doses in most of the studies.
A few precautions are necessary to take while using curcumin. (Read Side-effects & Precautions of Curcumin)
Curcumin may cause allergies in sensitive individuals. Please conduct a patch test before applying curcumin topically.
Curcumin may cause acid reflux in the prone individuals. Therefore, it should be consumed after a meal.
Large dose of curcumin can cause gastric discomfort like diarrhea, bloating, nausea etc. Therefore, it is advisable to start curcumin with low doses, and its intake should be avoided in case any severe gastric side-effects are observed.
Curcumin interferes in drug metabolism. Therefore, 3-4 hours gap must be maintained between taking curcumin and any medication. An expert’s opinion is best to take in this matter.
Curcumin may increase the risk of bleeding owing to its blood thinning activity. Therefore, people with bleeding disorders or on blood thinning medication should refrain from curcumin. (Read Is turmeric a blood thinner?)
Curcumin intake should be discontinued at least two weeks ahead of a surgery and after that as well.
Gallstone Patients should take curcumin supplements if advised by health practitioner.(Read Is turmeric safe in gallstones?)
Curcumin supplements must be devoid of contamination. Curcumin supplements can have contaminants such as heavy metals, harmful chemicals, fillers or additives. These contaminants may be a potent disease (such as cancer, ulcers, etc.) causing agents.
Curcumin supplements are excellent when combined with bioavailability boosters. Curcumin is poorly available to the body. Therefore, it is best to integrate curcumin with the agents like Bioperine which increase its absorption in the body.
A medical expert must be consulted before using curcumin supplements.
Curcumin is a great natural alternative for pain management.
The anti-nociceptive action is efficient in inhibiting the pain signalling mechanism triggered by a number of stimuli.
Its anti-inflammatory activity aids against the neuropathic and other inflammation related pain and reduces the hypersensitivity of the body tissues to various stimuli.
Curcumin can not only reduce pain but also prevent the pain caused due to nerve damage or neuropathic pain.
The pain relieving activity of curcumin is efficient in ameliorating several types of pain caused by different stimuli. These range from arthritic pain to postoperative pain.
Overall, curcumin has immense potential in the treatment and prevention of pain associated with numerous conditions.