Multiple sclerosis (MS) is a disease of the central nervous system, meaning it affects the brain and spinal cord.
In the most common type (known as relapsing remitting MS), symptoms come and go. These can run the gamut from mild tingling to more severe vision loss.
However, MS is tricky. Because so many other conditions can also cause similar symptoms, a hypochondriac could easily think they have it when they don't. On the other side, it can take years or even decades for people with MS to be diagnosed. Only a doctor can perform the appropriate tests to confirm whether these symptoms are indeed MS.
Fatigue
Some 80 percent of people with MS will experience fatigue at one point or another, but fatigue can have many causes. Some people experience “MS lassitude,” a very severe fatigue that occurs daily that tends to get worse as the day wears on.
“People describe it as unlike anything they’ve ever felt,” said Rosalind Kalb, vice president of the Professional Resource Center at the National Multiple Sclerosis Society in New York City.
Numbness
Numbness (or a lack of sensation in various parts of the body) is often one of the first symptoms to bring a person with MS to the doctor. Numbness can occur in the face, the body, or the arms and legs, and can interfere with walking, holding on to objects, and even chewing, if the numbness affects the face.
Sometimes the feeling—or lack thereof—progresses over hours or days, but it usually subsides on its own.
Tingling
Tingling is related to numbness and may feel like your arm, fingers, or toes are falling asleep, yet never quite waking up. Like other MS symptoms, this is a result of damaged nerves sending mixed signals to the different parts of the body.
People may also experience something called the “MS hug.”
“It feels like somebody is grabbing them very tightly around the midsection, but it’s not muscular,” Kalb, who is also principal author of MS For Dummies, said. “It’s a sensory phenomenon that feels like this tight banding.”
Balance and coordination problems
Movement problems are a hallmark of MS.
“Impaired nerve conduction means muscles are not behaving the way they used to,” Kalb explained.
People may report they feel suddenly weak in one limb or they may find objects slipping easily out of their hands. If there’s damage to the cerebellum, the part of the brain that controls balance, people might also be unsteady on their feet and prone to falling.
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Spasticity
Spasticity can involve both stiffness as well as involuntary muscle contractions. As a symptom of MS, it’s most common in the legs and may manifest as a mild feeling of tightness in the muscles or as more severe pain.
In extreme cases, spasticity can cause a person’s body to become distorted and twisted, almost as if they’re folded up like a pretzel. The symptom often goes hand-in-hand with weakness of the limbs or other parts of the body.
Vision problems
Like numbness, vision problems are one of the most common early symptoms prompting a person to visit the doctor. The problem can manifest as double vision, eye pain, blurred vision, or a scotoma (it looks like a hole in your vision).
These symptoms usually result from optic neuritis or inflammation of the optic nerve, said Dr. Mark Keegan, associate professor of neurology at the Mayo Clinic in Rochester, Minn. Although vision problems can interfere with working and driving, they do tend to resolve on their own.
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Pain
“The majority of people with MS do experience pain related to their MS,” Kalb said.
The pain is often the direct result of nerves damaged by the disease. If this is the case, the person may feel severe burning sensations in their legs, feet or hands, or might imagine a knife is stabbing the side of his or her face because the nerves on that side are inflamed.
But pain can also be musculoskeletal, resulting not from nerve damage, but from impaired gait that causes misalignment of the hips and spine.
Bladder dysfunction
Bladder problems in people with MS can manifest in two, seemingly opposite ways. Some people have difficulty emptying their bladder. That means urine stays too long in the bladder, leading to infection, discomfort, and a distended bladder.
Or people might have the opposite problem with the bladder responding to even the tiniest bit of fluid. “You’re always feeling like you have to go to the bathroom but there’s nothing there,” says Kalb. The brain is either telling the bladder it’s full when it’s empty, or signaling it’s empty when it’s full.
Constipation
The most common bowel problem related to MS is constipation.
“This is because the nerves and muscles are not doing what we most of the time take for granted, which is moving things efficiently through the system,” Kalb said.
The problem can be compounded if the person also has bladder dysfunction and is cutting back on water.
“That only contributes to the constipation problem,” Kalb said.
Dizziness and vertigo
Fortunately, dizziness and vertigo aren’t among the most common MS symptoms as they can be, Kalb said, “truly awful.” At their worst, people feel they “can’t get the world to stop spinning and have to stay in bed until it goes away,” she added.
The good news is that the symptoms often do go away and, for others, common drugs used to treat dizziness and vertigo in otherwise healthy people can be effective.
Sexual dysfunction
There are three types of sexual problems related to MS, and the first is direct neurological damage to the nervous system. For women, that means loss of sensation, loss of vaginal lubrication, and an inability to achieve orgasm. For men, it can mean sensory changes as well as difficulty getting and maintaining an erection and difficulty reaching orgasm.
In addition, people with MS might feel reticent about sex because they’re tired or are worried about bladder control. Some MS medications can also affect sexual function.
Depression
Not surprisingly, depression is common among people with MS. Changes in the immune system can contribute to depression, as can biochemical changes in the brain.
But simply living with a chronic, unpredictable disease can trigger depression.
“The most important thing for people with MS and their families to understand is that this is not about being weak or crazy or somehow emotionally damaged,” Kalb said. “This is a symptom of MS just like any other symptom that needs to be appropriately treated.”
Cognitive dysfunction
Cognitive dysfunction affects upwards of 60 percent of people with MS, Kalb said. The good news is that only specific areas are affected. This could be recent or “working” memory or the speed at which a person is able to process information. Or a person may have trouble focusing or multi-tasking.
Once these problems start, they often don’t go away, but they do progress slowly.
“With appropriate diagnosis and strategies for managing, people can stay ahead of it and use compensatory strategies,” Kalb said. Cognitive changes are severe for only a small percentage of people.
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Anxiety
This is the “poor second cousin to depression,” Kalb said. That’s because depression gets all the attention, though anxiety can be equally debilitating. Not only are there organic changes in the brain that result in anxiety, but the ongoing, uncertain nature of MS can be nerve-wracking.
MS can also involve mood swings and irritability, although the irritability may be a consequence of depression.
Emotional changes
About 10 percent of people with MS may experience “pseudobulbar affect” (PBA), a neurologic change that usually occurs in tandem with cognitive changes. Here, the expression of a mood or feeling is disconnected from how a person’s actually feeling so a person may have uncontrolled bouts of crying when they’re not actually sad or they may laugh hysterically at inappropriate times.
Speech and voice disorders
Up to 40 percent of people with MS experience problems with their voice or speech.
One possible problem is dysarthria, a motor speech problem that manifests as slurring, poor articulation of words, and speaking too loudly or too softly. Another possibility is dysphonia, a change in voice quality, such as sounding hoarse or nasal.
This article originally appeared on Health.com.