Multiple sclerosis (MS) and its treatments can sometimes affect blood sugar levels, causing them to soar too high or dip too low. If your blood sugar levels are abnormal, you may need to work with your doctor to help treat the issue. High or low blood sugar levels can lead to additional health problems. They may also be a sign of diabetes, a condition that occurs more often in people with MS than in the general population.

Many members of MyMSTeam have experienced blood sugar problems. “I have been nauseous quite a bit lately,” wrote one member. “My blood sugar is running a bit low.” Another member said, “I have hypoglycemia — low blood sugar. If I don’t eat, I get very sick.” A third member reported, “My biggest issue is that I have hypoglycemia. I had a crash tonight that took a lot out of me.”

Abnormal Blood Sugar Levels

Your levels of blood sugar, also called blood glucose, is affected by the foods you eat — in particular, foods that contain carbohydrates. Many types of foods contain carbohydrates, including bread, rice, cereal, potatoes, fruit, beans, and desserts. When you eat these foods, your body breaks down the carbohydrate molecules into sugar.

Your blood absorbs the sugar that you digest and carries it all around the body to different tissues, like organs and muscles. Cells take sugar from the blood and transform it into energy.

Having some sugar in the blood helps your body properly function. However, problems arise when blood glucose levels become too high or too low.

High Blood Sugar Levels

Your blood glucose levels rise after eating. Typically, this tells your pancreas that it’s time to make more insulin — a hormone that helps cells absorb sugar from the blood. As your cells use this fuel, your blood sugar levels decrease.

In some cases, the pancreas can’t make or use insulin properly. This means that the sugar does not enter the tissues, and it remains in the blood, leading to high blood sugar levels. This condition is called hyperglycemia. You have hyperglycemia if:

• Your blood sugar is more than 180 milligrams per deciliter (mg/dL) one to two hours after you eat a meal.
• Your blood sugar is more than 125 mg/dL when you first wake up in the morning, before eating or drinking anything.

If doctors confirm that you have hyperglycemia, you may have diabetes. If left untreated, hyperglycemia and diabetes can damage multiple tissues and organs, such as the eyes, kidneys, nerves, and blood vessels. You may also develop wounds that won’t heal and have an increased risk for having a heart attack or stroke.

Low Blood Sugar Levels

Your body has several ways of making sure your blood sugar levels don’t drop too low. Your liver is a main storage area for excess glucose and can release it into the blood when needed. Your body makes a hormone called glucagon that tells the liver when to release its stored sugar.

Certain medications or health conditions can interfere with these processes, causing blood glucose levels to drop too low. This condition, called hypoglycemia, occurs when your blood sugar levels are below 70 mg/dL.

Hypoglycemia can make you feel weak or dizzy. It can increase your risk of falling or getting into an accident. In serious cases, low blood sugar levels can cause you to have a seizure, pass out, or even die.

“Since I was in my teens, my [blood sugar levels] would run low, but now it drops fast and can get dangerously low in a short time,” commented one MyMSTeam member.

Possible Causes of Low or High Blood Glucose Levels

If you are living with MS, there are a few different factors that may affect how your body uses glucose. Abnormal blood sugar levels can be a result of the disease itself. Certain drugs for MS may also lead to high or low blood glucose levels. Finally, changes in your blood sugar levels may occur as a result of other unrelated factors.

Multiple Sclerosis

People with MS are 46 percent more likely to develop insulin resistance, a condition in which your cells can’t properly use insulin and don’t absorb sugar from your blood. If left untreated, insulin resistance can lead to high blood glucose levels and, eventually, type 2 diabetes. Diabetes is a condition characterized by ongoing high blood sugar levels and an inability of your body to make or use insulin.

It’s not fully clear why MS can change how the body uses sugar. Lifestyle factors may play a role. For example, people with MS may have a hard time being physically active, and a sedentary lifestyle is a diabetes risk factor. Other conditions that can increase diabetes risk include hypertension (high blood pressure), high cholesterol levels, and obesity.

There are also other links between diabetes and MS. Type 1 diabetes, a form of diabetes that is often diagnosed in children and teens, is an autoimmune disease, like MS. Having type 1 diabetes makes you three times more likely to develop MS. Additionally, certain diabetes drugs may help treat MS. Health experts don’t yet fully understand the link between blood sugar and multiple sclerosis, but research is ongoing.

Quite a few MyMSTeam members have reported living with both MS and diabetes:

• “I’m type 1 diabetic and my blood sugars go up and down like a yo-yo.”
• “I’ve had type 1 diabetes for a little over 21 years now, and just recently got diagnosed with MS. Juggling one disease was enough work, now this.”
• “I’m an insulin-dependent diabetic. During flare-ups, I often feel like my sugars are low when they are not.”

MS Treatments

Some MS treatments may also lead to blood sugar problems. Dimethyl fumarate (Tecfidera), a treatment for relapsing-remitting MS, may lead to high blood sugar levels in some people.

Several MyMSTeam members have discussed this drug’s effect on their blood sugar levels. “In my case, my blood sugars ended up really high multiple times, so I had to stop the Tecfidera. That happened once I moved to the full dose.”

Another member taking this medication shared, “I do blood work monthly, and my blood sugar has gotten higher each month.”

“My blood sugar is spiking eight hours after taking Tecfidera, causing debilitating nausea/vomiting,” reported an additional member.

High blood glucose levels are also a common side effect of steroids, which are anti-inflammatory drugs. Steroids such as methylprednisolone (Solu-Medrol) are sometimes prescribed to help treat MS relapses.

Some members report problems with blood sugar levels after using steroids. “Each time I have had a Solu-Medrol infusion, I have required insulin injections although I am not diabetic,” said one member. Another wrote, “When I am getting an infusion treatment, I watch my blood sugar closely as steroids will raise it.”

Other Potential Causes

Problems with blood sugar levels are most often caused by diabetes or medication. However, other less common causes also exist.

You may have high blood sugar due to factors like:

• Illnesses that affect hormone levels, such as Cushing’s syndrome
• Pancreatic disorders like pancreatitis or cystic fibrosis
• Medications such as diuretics (water pills)
• Gestational diabetes, which can occur during pregnancy
• Surgery

A person may develop low blood sugar levels as a result of fasting, skipping meals, or not eating enough carbohydrates. Additionally, getting more physical activity than usual can make levels drop. You can also get hypoglycemia as a result of drinking too much alcohol, having liver or kidney disorders, or experiencing hormone imbalances.

Symptoms of Hyperglycemia and Hypoglycemia

If your blood sugar levels are abnormal, you may notice certain characteristic symptoms. Symptoms of hyperglycemia, or high blood glucose levels, include:

• Unusually frequent urination
• Unusual thirst or hunger
• Blurry vision
• Headaches
• Tiredness
• Unexpected weight loss
• Wounds that take a long time to heal
• Frequent infections

Hyperglycemia can also lead to an emergency condition called ketoacidosis, in which your body starts creating toxic levels of molecules called ketones. Ketoacidosis leads to its own set of symptoms, including extreme thirst, fruity-smelling breath, nausea, vomiting, muscle aches, shortness of breath, dry mouth, and confusion. It can lead to coma or even death. Seek emergency medical care if you think you have ketoacidosis.

Symptoms of hypoglycemia, or low blood sugar levels, may include:

• Hunger
• Skipped heartbeats
• A fast heart rate
• Weakness, shakiness, or jitteriness
• Pale or clammy skin
• Increased sweating
• A tingling feeling in the face or tongue
• Anxiety, irritability, or confusion
• Blurry vision
• Fatigue

MyMSTeam members with blood sugar problems report a range of symptoms. “I was diagnosed with hypoglycemia in the ’90s,” wrote one member. “I had an attack at work. I started shaking, had cold sweats, and felt lightheaded.” Another member said, “I am having blood sugar issues and take Tecfidera. I’m having crazy blood sugar spikes early mornings and late afternoons causing nausea and vomiting.”

Some members report that blood sugar-related symptoms and MS symptoms overlap, which sometimes causes difficulty in telling the two conditions apart. “As someone with diabetes and MS, fatigue is common. I am continually dealing with it,” said one member. Another member wrote, “At first, and still sometimes, I can’t tell if it’s MS or diabetes. Some of the MS-related fatigue/dizziness is like low blood sugar symptoms.”

Are You Dealing With Abnormal Blood Sugar Levels?

If you notice possible symptoms of hyperglycemia or hypoglycemia, talk to your doctor. Simple laboratory blood tests can help measure your blood sugar and insulin levels and detect any abnormalities. You can also purchase a blood glucose test kit at a pharmacy to monitor your blood sugar at home.

Abnormal blood sugar levels can be a sign of diabetes. If you are diagnosed with the condition, lifestyle changes and medications can help keep the condition under control and improve your quality of life. Alternatively, your doctor may suggest changing your MS treatment plan if certain drugs are causing abnormal blood glucose levels.

Talk With Others Who Understand

MyMSTeam is the social network for people with multiple sclerosis and their loved ones. On MyMSTeam, more than 186,000 members come together to ask questions, give advice, and share their stories with others who understand life with multiple sclerosis.

Has multiple sclerosis affected your blood sugar levels? Have you experienced blood sugar drops or spikes? Share your experience in the comments below, or start a conversation by posting on MyMSTeam.