Not all MS symptoms build slowly. Some appear suddenly, last only a few seconds, and then vanish — only to return again and again. These are known as paroxysmal symptoms, and while they are less common than fatigue, vision problems, or mobility issues, they are well-documented in MS.

How common are they?

Studies suggest that 2–5% of people with MS experience paroxysmal symptoms, though some clinical reports place the number higher. They are most often seen in the early years of MS, and may even be a person’s first noticeable symptom. Importantly, they are often highly treatable once recognized — but because they are brief and strange, they are frequently misdiagnosed or dismissed.

Why they matter

Even though each episode may last just seconds, paroxysmal symptoms can occur in clusters dozens of times a day, making them very disruptive. They are not relapses and do not represent new damage, but they can…

Understanding neuropathic pain without visible cause

Many people living with multiple sclerosis (MS) report a distressing symptom: a sudden burning sensation in the legs, arms, back, or face—often without any visible trigger. There’s no rash, no injury, no heat source—just the intense, uncomfortable feeling of being burned.

This symptom is not imagined. It’s a form of neuropathic pain caused by damage to the nervous system, and it’s one of the many invisible but very real sensory symptoms of MS.

What Causes Burning Sensations in MS?

MS is a disease that damages the protective covering (myelin) around nerves in the central nervous system. When these nerves are affected—particularly those responsible for sensory input—they can misfire or send distorted messages to the brain.

Some people with multiple sclerosis (MS) describe the unsettling feeling of walking on gravel, marbles, or pebbles—even when the floor is completely flat and smooth. This unusual but common sensory symptom can be confusing, uncomfortable, and even dangerous, especially when it affects balance or walking confidence.

This symptom is a form of paresthesia—abnormal sensory input caused by damage to the nerves responsible for detecting pressure, position, and touch. Understanding the neurological cause behind this feeling can help people with MS manage it more effectively and protect their mobility.

What Causes the “Pebble” Sensation in MS?

This sensation is usually the result of demyelination—the process in which MS damages the protective coating (myelin) around nerves. When this occurs in the spinal cord, brainstem, or peripheral sensory pathways, it disrupts the brain’s ability to process accurate input from the feet.

Instead of registering flat pressure and smooth surfaces, the nervous system may…