If you’re living with multiple sclerosis (MS) and are experiencing new or worsening symptoms, you’ll need to know the underlying causes. And in some cases, symptoms of an MS relapse and symptoms of stroke can overlap, making it hard to tell them apart.

It’s critical to be able to tell the difference, especially because people with MS are at greater risk of having a stroke. Treatment for stroke is time-sensitive — the sooner you get treatment, the better off you’ll be.

Read on to learn about five ways to tell the difference between symptoms of MS or a stroke.

1. Timing Matters

When you’re worried about whether you’re having a relapse from MS or a stroke, the timing of your symptoms can provide a lot of insight. Most of the time, during a stroke, symptoms come on suddenly. One moment, you are functioning normally and the next moment, you’re not. Stroke symptoms typically come on within minutes to hours. During an MS relapse, however, symptoms generally develop over hours to days.

While timing can often be a good indicator of the difference between stroke and MS, it’s not always the case. For example, if someone is sleeping when a stroke or a relapse happens, the symptoms may not be recognized until the next day. At that point, you won’t know when the symptoms began.

The same is true if you miss the first signs, such as very mild weakness or numbness. Additionally, if someone is cognitively impaired (has trouble thinking or remembering things), lives alone, has difficulty expressing themselves, or if their new symptoms involve their speech or understanding, it might be impossible to get information about when symptoms began. Nevertheless, timing can serve as a good baseline for assessing the likelihood of a stroke.

2. Watch for Certain Symptoms

Although there is some overlap between many symptoms from an MS relapse and stroke –– because both affect the nervous system –– there are a few symptoms that are not shared nearly as often.

Sometimes, a stroke can cause people to lose their ability to speak, either through slurring speech or putting words together that don’t make any sense (also called word salad). Usually, a family member will notice this change. A stroke can also cause difficulties in understanding speech. Sudden difficulty with speaking and/or understanding are symptoms seen in stroke much more often than speech symptoms seen during an MS relapse.

Certain symptoms are more common during an MS relapse from a lesion (damage or inflammation in the central nervous system) as compared to a stroke. Problems with managing your bowels and bladder, pain, and muscle spasms are rarely seen during a stroke. If you normally have these symptoms during an MS flare, it’s more likely you’re having another flare-up than a stroke.

Sometimes, it’s hard to tell the difference based on symptoms alone. Symptoms that are seen in both MS flares and stroke can include:

• Weakness and/or numbness of the arms, legs, or face
• Changes in vision, including vision loss or blurred vision
• Difficulty walking
• Problems with balance or coordination
• Headache
• Dizziness
• Confusion

3. Your Background May Matter

Generally speaking, MS and stroke tend to affect different groups of people. Stroke is more common in men 65 years of age and older, and MS is more commonly diagnosed in women between 20 to 50 years of age. Research from the National Institutes of Health shows that you are twice as likely to have a stroke if you are African American or Hispanic, but you are at higher risk of developing MS if you are white or of European descent.

According to the Centers for Disease Control and Prevention, approximately 1 in 7 strokes occur in people under age 45, and stroke affects people of all racial and ethnic backgrounds. This information just provides an overview of trends so you can get a better idea of the differences in demographics (populations and characteristics) most common among both groups.

4. Your Medical History Is Important

Many risk factors are known to significantly increase your risk for stroke. These include high blood pressure (also called hypertension), high cholesterol, heart disease, diabetes, and sickle cell disease. Your family history is also important. If there is a history of stroke in your family, and especially if combined with unhealthy lifestyle factors, your risk for stroke is higher.

Drinking excessive alcohol or using drugs also raises your risk for stroke. Importantly, if you’ve previously had a stroke or a transient ischemic attack (TIA, also known as a “mini-stroke”) in the past, the risk of having a second stroke is higher.

MS has different risk factors than stroke. A history of certain viruses, especially Epstein-Barr infection, having another autoimmune disease, or having a family history of MS puts you at higher risk for getting MS. Living in regions of temperate climate and areas further from the equator also increases your risk of being diagnosed with MS because there is less ultraviolet light in those areas.

Both smoking and obesity are risk factors for MS and stroke. And if you have MS, you’re also at a higher risk of stroke.

Eating a balanced diet, having an active lifestyle, and quitting smoking are all important for reducing your risk of stroke and the severity of your MS symptoms.

In addition to MS, people with acute migraine headaches, very high blood pressure, brain tumors, and seizures can show signs and symptoms similar to a stroke.

5. When To Seek Emergency Care

If you are living with MS and worried about your symptoms, it’s always best to talk to your neurologist. However, there are certain times and symptoms that should prompt you to go to the nearest emergency room as soon as possible. These include any sudden onset of:

• Weakness, especially on one side of the body
• Numbness or tingling
• Vision problems, especially in one eye
• Confusion
• Slurred speech or nonsensical words
• Difficulty walking
• Severe headache
• Difficulty staying awake or unconscious

MS can vary quite a bit from person to person, especially in the types of symptoms and their timing. Because a stroke is an emergency –– and can be life-threatening –– it’s critical to be evaluated by an emergency room (ER) doctor right away. In addition, the timing of the treatment window is very limited in ischemic stroke, the type of stroke that is usually caused by a clot. So the faster you get to the ER, the higher the chance of a good outcome.

If you think you might be having a stroke or if you’re not sure whether it’s MS or a stroke, contact your neurology provider right away or get emergency medical assistance. Acting quickly can make a big difference and possibly even save your life. Don’t wait when you have these symptoms — seek medical help without delay.

Talk With Others Who Understand

MyMSTeam is the social network for people with MS and their loved ones. On MyMSTeam, more than 198,000 members come together to ask questions, give advice, and share their stories with others who understand life with MS.

Are you living with MS and worried about how to tell the difference between MS and stroke? Share your experience in the comments below, or start a conversation by posting on your Activities page.