Have you ever felt an itch that just wouldn’t go away, and the more you scratch, the more it itches? Although itching for no apparent reason may sound like a psychological problem, it’s a very real phenomenon for people with multiple sclerosis (MS).
It’s not uncommon for people with MS to experience strange sensations (dysesthesias) like pins and needles, burning, stabbing, or tearing. Itching (pruritus) is another symptom of MS.
These sensory disturbances are often early signs of MS and occur in about 20 to 50 percent of people with MS, according to the Multiple Sclerosis Foundation.
MS Isn’t a Skin Condition, So Why Do I Itch?
In MS, the immune system mistakenly attacks myelin, the protective coating that surrounds nerves. Inflammation causes lesions to form, disrupting signals between the brain and the rest of the body. Symptoms vary according to the location of the lesions. Sometimes demyelination, the process in which myelin is destroyed, can cause electrical impulses that create strange sensations.
Temporary neurological disturbances are called paroxysmal symptoms. They’re generally more fleeting than the symptoms of full-blown MS attacks. Itching is just one potential sensory disturbance of MS. As with other symptoms of MS, itching may come on suddenly and occur in waves. It may last a few minutes or for much longer.
There may be other causes of MS-related itching as well. Some disease-modifying medications are administered by injection, which may cause temporary skin irritation and itching at the injection site. An allergic reaction to medications like interferon beta-1a (Avonex) also may result in itching.
An allergic skin reaction to natalizumab (Tysabri), a drug that is given intravenously, may cause the skin to itch. In clinical trials, one of the common side effects of the oral medication dimethyl fumarate (Tecfidera) was the sensation of itching.
How Can I Stop the Itching?
If itching is mild, no treatment is necessary. In fact, over-the-counter topical treatments are of no use for this type of itching.
If itching is severe, prolonged, or begins to interfere with daily living, talk to your doctor. Medications used to treat dysesthetic itching include anticonvulsants, antidepressants, and antihistamine hydroxyzine.
If your itching is accompanied by an external rash or visible irritation, see your doctor. This may be a sign of an allergic reaction or infection and is probably not related to MS disease activity.
Are There Any Long-Term Risks of Itching?
MS-related itching is irritating and distracting, but it usually doesn’t pose a long-term risk.
Itching creates a strong desire to scratch, but this can actually increase the feeling of itchiness. Vigorous scratching can break and damage the skin, which can lead to infection.
The good news is that in most cases, no treatment is necessary and symptoms will subside on their own.