Triggers of MS symptoms, such as vitamin deficiencies and stress, may contribute to worsening symptoms and vary from person to person. Identifying and avoiding your MS triggers may help prevent relapses.


Multiple sclerosis (MS) triggers include anything that worsens your symptoms or causes a relapse. You can often avoid your MS triggers once you know what they are.

In addition to working to avoid your triggers, other strategies can help reduce your relapse risk, including regular exercise and a balanced diet.

You might be more sensitive to some of the more common triggers than others. You may have some triggers in common with others who have MS, as well as some that are unique to you.

Over time, you may be able to identify triggers that make your symptoms worse. Keeping a journal of your symptoms, when they occur, and what you were doing beforehand can help you identify potential triggers.

Here are some of the most common triggers you may experience with MS and tips to avoid them.

Having a chronic disease like MS can be a source of stress. But stress can also stem from other sources, including work, personal relationships, or financial worries. High stress levels may worsen MS symptoms, including fatigue.

How to avoid

Find a relaxing, stress-reducing activity that you enjoy. Yoga, meditation, and breathing exercises are all practices that may help reduce stress and reduce the risk of making symptoms worse.

Talking with a mental health professional may also help you learn to reduce and manage stress. For example, cognitive behavior therapy (CBT) can teach you new strategies to both think about and handle situations that cause stress.

The heat from indoor heating systems, the sun, and artificially heated saunas and hot tubs may be too intense for some people with MS. They can often lead to a period of exacerbated symptoms.

How to avoid

If heat is a trigger for you, skip high-heat environments like saunas, hot yoga studios, and hot tubs. Keep your home cool and run extra fans if necessary.

On hot days, avoid direct sunlight, wear loose, light-colored clothes, and stay in the shade as much as possible. Personal fans, clothes with cooling fabrics, and staying hydrated may also provide some relief from heat.

Pregnant people with MS may experience a relapse after delivering their baby. The chance of relapse is elevated in the first 3 months after delivery.

How to avoid

You may not be able to prevent a flare after childbirth, but you can take steps to reduce its severity and impact. In the immediate days after giving birth, try to rest and care for yourself as much as possible. This can help your body recover more efficiently. It may also be helpful to reach out to family and friends for support as you recover.

According to some research, exclusive breastfeeding may have a potential protective effect against postpartum flare-ups.

However, if you’re taking disease-modifying medication, nursing may potentially be harmful to your baby. Talk with an OB-GYN and neurologist about your post-birth options. Some people may choose to stop some medications or use other therapies during pregnancy and nursing.

Infections can cause MS flare-ups, and MS is also more likely to raise your risk of certain types of infection.

For example, people with impaired bladder function are more likely to develop urinary tract infections. This infection may exacerbate other MS symptoms.

Infections like the flu or common cold can also worsen MS symptoms.

Some medications may also affect your body’s immune function.

How to avoid

Protecting yourself from illness and practicing behaviors that reduce your risk of infections is an important part of treatment for MS.

You can do this by washing your hands during cold and flu season and avoiding people who are ill, especially when you’re experiencing a flare. You can also take other precautions, such as wearing a mask in public spaces and following food safety guidelines to prevent foodborne illnesses.

Talk with a doctor if you think you’re getting sick.

Vaccines are generally safe — and recommended — for people with MS. Certain vaccines that contain live pathogens can potentially lead to an infection for people who have a weak immune system.

If you’re taking certain medications, a doctor may also recommend you postpone vaccination.

How to avoid

Talk with a neurologist about any vaccine you’re considering. Some vaccines, like the flu vaccine and COVID-19 vaccine, may help you prevent a future flare infection. A doctor can help you determine which vaccinations are safest for you.

One review of research notes that lower vitamin D levels are associated with a higher risk of flare-ups than adequate vitamin D levels and that adequate vitamin D levels may be protective against developing MS.

But a newer study points out that more research is needed to determine whether low vitamin D levels cause flare-ups or occur with them for another reason, such as lack of sun exposure during relapses or other factors.

How to avoid

A doctor may monitor your vitamin D levels regularly as part of routine lab work. If you have a vitamin D deficiency, they may recommend getting more vitamin D from food and safe sun exposure.

They may also recommend vitamin D supplements. Be sure to talk with a doctor about the safest supplement options before trying any. Doctors typically recommend opting for a supplement brand that is subject to third-party testing, as supplements are not regulated by the Food and Drug Administration (FDA) the way medications are.

Sleep is vital for your health. Your body uses sleep as an opportunity to repair your brain and heal other areas of damage. If you aren’t getting enough sleep, your body doesn’t have this downtime. Excess fatigue can trigger symptoms or make them worse.

MS can also make sleep more difficult and less restful. Muscle spasms, pain, and tingling may make it difficult to fall asleep. Some common MS medications may also interrupt your sleep cycle, preventing you from getting shut-eye when you feel tired.

How to avoid

Talk with a doctor about any sleep problems you may have. Sleep is vital to your overall health, so this is an important area of treatment and observation. They can rule out other conditions and give you tips for managing fatigue and getting better sleep.

You can also improve your sleep hygiene by maintaining consistent sleep and wake times, avoiding exercise and stimulants like caffeine in the hours before bed, and making sure your room is dark and a comfortable temperature.

A balanced diet and regular exercise support your overall health, reduce flare-ups, and ease MS symptoms. A diet high in processed foods is unlikely to provide you with the high quality nutrition your body needs.

How to avoid

Work with a dietitian to develop an eating plan you can stick to. Focus on good sources of protein, healthy fats, and carbohydrates.

While research isn’t yet clear on the best diet for people with MS, studies suggest eating nutritious foods, such as vegetables, whole grains, beans, nuts, and seafood, can have a positive effect.

Cigarettes and other tobacco products can increase your symptoms and make progression happen more quickly. Likewise, smoking is a risk factor for various medical conditions that can worsen your overall health, including lung disease and heart disease.

A review of research notes that tobacco smoking is associated with more severe MS. It also may speed up disability and disease progression.

How to avoid

Quitting smoking, even after your diagnosis, can improve your outcome with MS. If you smoke, consider talking with a doctor about effective smoking cessation options.

Certain medications have the potential to worsen your MS symptoms. Your healthcare team likely has steps in place to make sure you don’t take medications that may trigger a flare-up, but you can also talk with your doctor about the medications they prescribe.

At the same time, your neurologist may closely watch the number of medications you’re taking. Medications can interact with one another, which can cause side effects. These side effects could trigger an MS relapse or make symptoms worse.

How to avoid

Report all medications, including supplements and over-the-counter drugs, you take to every doctor who provides care for you. They can help you narrow down your list to the necessities so you can prevent problems.

Sometimes, MS medications can cause side effects. They may also not seem as effective as you’d hope, but this doesn’t mean you should stop taking the medications without the prescribing doctor’s approval. Stopping them can increase your risk of flare-ups or relapses.

How to avoid

Avoid stopping any medication without talking with the doctor who prescribed it or a member of their team.

Though you may not realize it, these treatments are often working to prevent damage, reduce relapses, and stop new lesion development. In some instances, stopping medications rather than gradually reducing them can have dangerous side effects.

Fatigue is a common symptom of MS. If you have MS and push yourself to go without sleep or overexert yourself physically or mentally, you may experience flare-ups. Exertion and fatigue can trigger a relapse or make flares last longer.

How to avoid

Take it easy on yourself and listen to your body’s cues. Slow down when you’re feeling tired. Rest as long as you have to. Pushing yourself to the point of exhaustion can make recovery more difficult.

If you’re feeling fatigued, you can talk with a doctor about options available to you for support.

What causes MS symptoms to flare?

There are some common MS triggers, and you might notice that some have a more noticeable effect on your symptoms. They may include heat, illness, and diet, among others.

If you experience a worsening of symptoms, noting potential triggers may help you identify and avoid them in the future.

Can MS be triggered by something?

Yes, environmental and personal factors can trigger MS. These may include stress, illness, and medication changes, among others.

What foods cause MS flare-ups?

If you have MS, you may want to avoid foods that can contribute to inflammation, such as fried foods, foods that are high in unhealthy fats, foods high in added sugar, and highly processed foods.

When you have MS, you may need to make a few lifestyle changes to prevent relapses and reduce your symptoms. You may be able to easily avoid some triggers, but others may require more work.

Talk with a doctor if you’re having difficulty managing your MS symptoms.