When you have multiple sclerosis (MS), maintaining nutrient levels through healthy eating may help you manage your symptoms. Potassium is one vital nutrient, and having low levels may result in health problems for people with MS.

Several members of the MyMSTeam community have been discussing the role of potassium in their lives. After describing their low potassium levels, one MyMSTeam member asked, “What causes low potassium? What foods did you eat to help bring it back up?”

Another member said, “I only started having problems with my potassium when they started suspecting me for MS. Are they really related?”

MS is an inflammatory autoimmune disease. The immune system targets and destroys parts of the central nervous system, including the brain and spinal cord. In a process known as demyelination, the fatty sheaths (myelin) that protect the nerves are degraded, resulting in a breakdown of communication between the brain and nerves. This breakdown ultimately leads to many of the symptoms of MS, including fatigue, vision problems, cognitive decline, and impaired muscle function.

Potassium is an electrolyte because it carries a small electrical charge. Your body uses this electrolyte to help maintain fluid levels inside cells. However, because it carries an electrical charge, potassium also plays an important role in transmitting nerve signals and allowing muscle contraction.

Symptoms of Hypokalemia

Low potassium, known as hypokalemia, occurs when potassium levels in the blood drop below what is considered normal. Normal levels of potassium vary slightly but can range anywhere from 3.5 to 5.1 millimoles per liter of blood. When levels drop below 2.5 millimoles per liter, this is considered serious.

If you have low potassium levels, you may experience the following symptoms:

• Muscle twitches
• Muscles weakness and cramping
• Paralysis of muscles
• Abnormal heartbeat rhythms
• Constipation
• Fatigue
• Tingling and numbness

You may notice that several of the symptoms of hypokalemia involve muscle function. Due to the overlap of muscle symptoms, people with MS may find it difficult to distinguish between symptoms of low potassium and MS symptoms.

Although there is some overlap between MS and low potassium symptoms, there are distinctions between what causes muscle weakness in the two conditions. When you have low potassium, you don’t have enough electrical charge to effectively send signals to your nerves. With MS, however, the coating of the nerves is damaged. Although this damage also results in a loss of nerve signaling, it is not necessarily because you don’t have enough potassium.

Causes of Low Potassium in MS

Many things can cause low potassium levels in the blood, including both general and MS-related triggers.

General Causes of Low Potassium

Although not specific to MS, several general factors can contribute to low potassium levels:

• Medications and antibiotics
• Laxatives and diuretics
• Diarrhea and vomiting
• Eating disorders
• Kidney disease
• Excessive sweating
• Overactive adrenal glands (hyperaldosteronism)

Can MS Directly Cause Hypokalemia?

The symptoms of MS and low potassium can be similar. However, it is unclear if MS can directly lead to lower potassium levels.

One study found that some people with MS make antibodies that bind to potassium channels, which are pores in your cells that allow potassium to enter them. However, this does not necessarily mean that MS causes changes in potassium levels. Further research is needed to more effectively research any possible links between MS and potassium levels.

How MS Indirectly Lowers Potassium Levels

Although there is little evidence to suggest MS directly changes potassium levels, there are many ways having MS may indirectly contribute to hypokalemia. For example, medications used to treat MS or symptoms of MS may lead to lower potassium levels.

Corticosteroids, including prednisone and methylprednisolone (Solu-Medrol), are used to treat MS relapses. Side effects of prednisone include a decrease in blood potassium levels. Meanwhile, methylprednisolone can cause increased sweating, which is a general cause of hypokalemia.

Treatment of MS can include a class of drugs known as disease-modifying therapies (DMTs). DMTs work by targeting and limiting your immune cells and immune response. Although DMTs effectively slow the progression of MS, they can also put you at an increased risk of infection. Antibiotics used for these opportunistic infections can lower the levels of potassium in your blood.

According to the National Multiple Sclerosis Society, people with MS often experience swollen legs and ankles, known as lymphedema. One way doctors combat this type of fluid buildup is by prescribing diuretics (water pills). Water pills help your body remove excess fluid through urination. By flushing out extra water, diuretics also have the side effect of reducing your potassium levels.

In addition, it’s common for people with MS to experience constipation. Laxatives are an easily accessible and relatively safe way to treat constipation. However, laxative overuse has been linked to low potassium levels in the blood.

Managing Low Potassium

If you’re experiencing low potassium levels, there are several ways to bring your levels within a normal range.

Dietary Forms of Potassium

Typically, people get the required amount of potassium through their diets. Many fruits and leafy vegetables are great sources of potassium. Eating the following potassium-rich foods may help manage your low potassium levels:

• Potatoes — Both regular and sweet
• Legumes — Most kinds of beans and lentils.
• Leafy greens — Spinach, kale, or Swiss chard, for example
• Fruits — Bananas, as well as dates, prunes, and oranges
• Fruit juices — Particularly orange, prune, and carrot juices
• Seafood — Tuna, salmon, and mackerel
• Dairy — Milk and yogurt
• Others — Tomatoes and avocado in particular

A good diet can provide several health benefits (including increased energy) and may also help with your MS symptoms. Remember to talk to your neurologist before making any significant dietary changes.

Nutritional Supplements

If you’re unable to increase your potassium levels through diet alone, you may consider using potassium supplements. These supplements are available over the counter and come in many forms including pills, tablets, powder, liquid, and multivitamins.

Although supplements may provide relief from low potassium, they may pose risks to your health. Potassium supplements can lead to too much potassium in the blood, known as hyperkalemia, which can result in muscle cramping, tingling, numbness, and chest pain.

As people age, the kidneys become less efficient at eliminating potassium from the body. This means older people are at a higher risk of hyperkalemia if they begin taking supplements.

Some MS medications, such as interferon beta-1a (Avonex) or interferon beta-1b (Betaseron), are risk factors for hyperkalemia. This is because they have been associated with elevated levels of potassium in the blood. Therefore, people with MS who are using these medications may need to avoid potassium supplements.

Don’t forget to talk to your doctor before starting any new supplements. They’ll be your best resource for understanding how potassium may interact with your current medications and how it may affect your MS. If you begin taking any supplements, be sure to follow up with your doctor regularly to monitor your potassium levels.

Talk With Others Who Understand

MyMSTeam is the social network for people with MS 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.

Do you have hypokalemia, or are you curious about how potassium might affect your MS? Share your experience in the comments below, or start a conversation by posting on your Activities page.