context: People with multiple sclerosis ( MS) tend to have their first symptoms between the ages of 20 and 40. Usually the symptoms get better, but then they come back. Some come and go, while others linger. No two people have exactly the same symptoms. You may have a single symptom, and then go months or years without any others. A problem can also happen just one time, go away, and never return. For some people, the symptoms get worse within weeks or months. Keep track of what's happening to you. It'll help your doctor monitor your disease and help her understand how well your treatment works. See More: A Visual Guide to Multiple Sclerosis For many people, the first brush with what's later diagnosed as MS is what doctors call clinically isolated syndrome ( CIS). This episode of neurological symptoms usually lasts 24 hours. It happens when your immune system mistakenly tells your body to attack myelin, the protective sheath over nerve cells in your brain and spine. You may hear your doctor call this demyelination. It causes scars, or lesions, that make it harder for signals to travel between your brain and your body. There are two types of CIS: Monofocal episode: You have one symptom. Multifocal episode: You have more than one symptom. The most common symptoms in CIS are: Optic neuritis: This condition damages the nerve that connects your eye to your brain. It usually affects just one eye, but in rare cases, it involves both. You might notice: Blurry vision Colors appear dull Pain in your eye, especially when you move it Numbness & Tingling: It usually affects your legs. You might feel: An electric shock-like feeling when you move your head or neck. It may travel down your spine or into your arms or legs. Numbness, often in your face Tingling Not everyone who has CIS will get MS. The odds are higher if you have lesions in your brain from loss of myelin. If you have another CIS or other MS symptoms later, your doctor will do a test called an MRI that takes a picture of your brain to look for them. These come from ongoing damage to your myelin. They aren't pleasant, but your MS treatment team can help you keep most of them under control with medication, rehabilitation, and other tactics. The most common symptoms are: Bladder and bowel problems: You may have to pee more often, need to go at night, or have trouble emptying your bladder fully. Bowel issues like constipation are also common. Clumsiness or lack of coordination: MS can make it hard to get around. You might have: Trouble walking A hard time keeping your balance Changes in your gait Dizziness: You may feel lightheaded. You probably won't have vertigo, that feeling that the room is spinning. Emotional changes and depression: It's tough to adjust to the idea that you have a chronic disease, let alone one that's hard to predict and that will take a physical toll. Fear of the unknown can make you anxious. Plus the disease damages nerve fibers in your brain, and that can affect your emotions. So can medications, like corticosteroids, used to treat MS. Eye problems: In addition to the optic neuritis that comes with CIS, MS can cause: Nystagmus: involuntary eye movements Diplopia: double vision Fatigue: You may feel very tired. It often comes on in the afternoon and causes weak muscles, slowed thinking, or sleepiness. It isn't usually related to the amount of work you do. Some people with MS say they can feel tired even after a good night's sleep. Heat-related problems: You might notice them as you warm up during exercise. You could feel tired and weak or have trouble controlling certain body parts, like your foot or leg. As you rest and cool down, these symptoms are likely to go away. Muscle spasms : They usually affect your leg muscles. They're an early symptom for almost half the people with MS. They also affect people with progressive MS. You might feel mild stiffness or strong, painful spasms. Sexual troubles: These include vaginal dryness in women and erection problems in men. Both men and women may be less responsive to touch, have a lower sex drive, or have trouble reaching orgasm. Speech problems: MS could cause long pauses between your words and slurred or nasal speech. You might have swallowing problems as the disease advances. Thinking problems: It might be hard to focus from time to time. This will probably mean slowed thinking, poor attention, or fuzzy memory. Some people have severe problems that make it hard to do daily tasks, but that's rare. MS doesn't usually change your intellect or ability to read and understand conversation. Tremors: About half of people with MS have them. They can be minor shakes or so intense it's hard to do everyday activities. Trouble walking: MS can cause muscle weakness or spasms, which make it tough to walk. Balance problems, numb feet, and fatigue can also happen. Unusual sensations: In addition to the pins and needles sensation that's part of CIS, you might also have severe itching, burning, stabbing, or tearing pains. You could feel a tightness around your ribs or upper belly known as the MS hug. Doctors call these uncomfortable symptoms dysesthesia. These are problems created by your primary MS symptoms, not by damaged myelin. Not being able to empty your bladder can lead to a bladder infection. If you have trouble walking and are often fatigued, you're likely to become less active. That can take a toll on your muscle tone, make your breathing shallow, and even affect your bone density. Doctors can treat secondary symptoms, but the goal is to avoid them by treating the primary symptoms. These are the social, psychological, and job-related problems of life with MS. If MS makes it hard for you to walk or drive, you may not be able to do your job well. Because it's tough to get around and hard to talk to people about what life with a chronic disease is like, you may not be as social as you once were. You could get depressed. It's a byproduct of the changes MS makes in your brain and in your life. Because MS varies so much, it's best not to compare yourself with other people who have it. Your experience is likely to be different. Most people learn to manage their symptoms and can keep leading full, active lives.