Multiple sclerosis, a chronic debilitating disease caused by damage to the myelin sheath of nerves in central nervous system (brain, spinal cord and optic nerve). This progressive autoimmune disease leads to inflammation and scarring of nerve sheath fibers at multiple levels in the central nervous system causing exposure of nerve fibers. The resulting nerve impulse conduction abnormality is responsible for all the varied symptomatology in multiple sclerosis.
The symptoms of multiple sclerosis are diverse and each case in unique. The various presenting symptoms include, fatigue, numbness, muscle spasms, tingling, pain, seizures, vision problems, headache, cognitive dysfunction, speech problems, breathing problems, dysphagia, dizziness, depression, bladder dysfunction, bowel changes, hearing problems, muscle spasticity, tremors and reduced sex drive. Although, not all the symptoms will be present in a patient, some symptoms will be exacerbated and some of the symptoms might be absent.
Is Itching A Sign Of MS?
In general, itching or pruritus is associated with allergy, drug reaction or tissue infection seen in systemic diseases; however, in multiple sclerosis itching is neurologic in nature. Although, itching is present in multiple sclerosis, it is a rare sign. When present in MS, it is a form of dysesthesia. Dysesthesia is any type of abnormal sensation found in patients of MS, which include burning, stabbing, pins and needles, electrical, prickling or tearing pain.
Pruritus when found in multiple sclerosis, is mostly paroxysmal in nature, mostly occurring at night, often waking patients from their sleep. Pruritus in MS is consistent with other paroxysmal attacks, such as of seizures, which also last between several seconds to minutes.
Previous studies have shown that itching in patients is usually sudden and abrupt in origin; the duration is usually short lived and lasts for several seconds to minutes. Itching is not persistent and in nature and scratching the area has no effect on itching. Itching is usually felt about five to six times a day and sometimes even more. The attack of itching is felt symmetrically and segmentally on face, trunk and/or extremities. The itching is mostly associated with pain sensations and may either follow pain or precede pain sensations in that particular area.
Although, pruritus is seen in MS, it is not clear as to the exact cause of it. There have been various theories around this and what can be considered coherent here is that these paroxysmal pruritus attacks are triggered by movement or some kind of sensory stimuli.
Pruritus can suddenly occur when there is movement of arm or while walking. It is a well established fact that MS is aggravated by heat, so when temperature is elevated by 0.5-1.0 degree Celsius at night, these paraoxysmal attacks of pruritus commonly occur. Heat is known to produce itch; however, the itching in MS is not generalized, it is localized to particular skin areas.
Research has supported close relation between pain and itching in MS patients as they have noted that pain and itching have been present in the same localized area. It is also noted that C fibers are associated with itching and burning and delayed pain. Stimuli with low frequency activity is associated with itch, whereas, stimuli with high frequency activity has been associated with burning and delayed pain. Thus, there exists a close relation between pain and itching.
Pruritus in MS is not associated with any kind of allergy so regular medications for itch or allergy, such as cortisone, Benadryl or anti-histamines are not effective to control this sensation. MS related itch is neither bettered by scratching. Since, the itch is associated with abnormality in nerve conduction and has neurogenic origin, medications targeting nerve impulses are only effective for them.
Carbamazepine, which is anti-epileptic or anti-convulsant, is found to be effective in controlling pruritus associated with MS. In addition, carbamazepine is also used to relieve certain nerve pain, including that of trigeminal neuralgia. This further, supports the theory that pain is closely associated with itching in MS.
Also Read:
- Multiple Sclerosis (MS) or Disseminated Sclerosis: Types, Risk Factors, Symptoms, Treatment
- Special Diets For Multiple Sclerosis (MS)
- Alcohol and Risk of Multiple Sclerosis: Is there a Link?
- How is Transverse Myelitis Connected to Multiple Sclerosis?
- Can Medical Marijuana Treat Multiple Sclerosis or MS?
- Common Symptoms of Multiple Sclerosis in Women
- How Do You Get Multiple Sclerosis?
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