What Causes Fibromyalgia to Flare Up?

Fibromyalgia flare-ups can be caused by various factors such as stress, injury, illness, hormonal changes, changes in treatment or routine, diet, lack of sleep, overdoing it, and even changes in the weather!

All these factors disrupt the body's pain system, which involves the nervous, immune, and endocrine systems. In fibromyalgia, this pain system is already sensitive, so any disturbance leads to an extreme reaction, causing symptoms to flare.

Identifying your triggers are critical to successfully managing your fibromyalgia, so in this article, we'll explore the most common causes for fibromyalgia flare-ups.

Why does stress trigger fibromyalgia flare-ups?

Stress causes fibromyalgia flare-ups primarily due to the way it affects the body's nervous system. In fibromyalgia, the nervous system is already hypersensitive, and stress exacerbates this sensitivity. When stressed, the body prepares itself for “fight or flight” response, and releases hormones like cortisol and adrenaline. This hormonal surge can heighten the nervous system's reactivity, leading to an amplification of danger signals, which is a central characteristic of fibromyalgia – and your pain dial is turned up – sometimes to the MAX level!

Additionally, stress can disrupt sleep and worsen fatigue, both of which are common in fibromyalgia. Poor sleep can make the body more sensitive to pain, creating a vicious stress-pain cycle where stress leads to poor sleep and increased pain, which in turn further increases stress responses!

An infographic of a circle showing the pain stress cycle - Pain causes a stress response which causes the nervous system to become sensitized which dials up the pain dial creating more stress and pain - and on it goes!

Why do I get a flare when I am sick?

When you're sick, your fibromyalgia may flare up because illness activates your immune system. This reaction involves releasing chemicals and hormones to fight the infection, which can cause inflammation and make your nervous system more sensitive. Since people with fibromyalgia already have a nervous system highly sensitive to pain, this increased immune response can worsen fibromyalgia symptoms, such as more pain and fatigue. In short, your body's effort to fight off sickness can overburden your sensitive systems in fibromyalgia, leading to more intense symptoms.

Recent research indicates that COVID-19, by triggering the immune system and causing inflammation, can exacerbate fibromyalgia symptoms due to their shared characteristics, intensifying pain and fatigue in those with fibromyalgia1.

I’ve changed medications and now have a flare-up!

Changing medications can lead to flare-ups for several reasons. First, the body may have adapted to the previous medication, and altering this disrupts the body’s homeostasis - the balance of physiological processes. Second, the new medications can introduce side effects or interact differently with the body's chemistry. For individuals with fibromyalgia, who often have a heightened sensitivity to physical changes, this can lead to an increase in symptom severity, including pain, fatigue, and cognitive difficulties, until the body adapts to the new treatment.

Additionally, if the change involves reducing or discontinuing a medication that was managing fibromyalgia symptoms, this might lead to a resurgence or worsening of those symptoms until the new medication starts to take effect, or an effective alternative treatment is found.

It's important for individuals with fibromyalgia to consult healthcare professionals when changing medications and to monitor their symptoms closely during the transition.

What hormonal changes can trigger a fibromyalgia flare-up?

Hormonal fluctuations, particularly of estrogen and progesterone, can impact fibromyalgia symptoms. These hormones, particularly prevalent in women, can fluctuate during the menstrual cycle, pregnancy, postpartum, and menopause. Lower levels of estrogen, for example, during menstruation or menopause, are often associated with increased fibromyalgia symptoms. Hormones are believed to be a contributing factor to the higher prevalence of fibromyalgia in females compared to males2.

Stress has also been shown to decrease estrogen levels3, and produces cortisol which has been shown to make pain and fatigue associated with fibromyalgia worse in high amounts. It’s no wonder that stress is one of the most common triggers for a flare-up!4

Other hormone influences to watch out for that can worsen fibromyalgia symptoms or cause flare-ups are imbalances in thyroid and insulin5.

If you suspect hormonal fluctuations are causing your flare-up, speak to your doctor for guidance and management.

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Can travelling cause a fibromyalgia flare-up?

A wonderful holiday, relaxing by the beach, exploring the sights - or stuck in your hotel room with a flare-up? Yes, it can and does happen. Travelling changes your normal routine and it can often involve long periods of sitting, waiting, different foods or weather – all possible triggers for your fibromyalgia symptoms. Our nervous systems are calmed and soothed by routine because of a sense of predictability and control. Take a trip and the body’s regulatory systems struggle to adapt to new environments and schedules.

Can food cause fibromyalgia flare-ups?

Certain foods can cause fibromyalgia flare-ups due to the body’s reactions to specific ingredients or food groups. For example, studies have shown that non-celiac gluten sensitivity may be an underlying cause of fibromyalgia6 and so it makes sense then that, for some people, an exposure to gluten may be a possible flare-up trigger.

Other potential triggers to pain and fatigue flares are high in sugar, unhealthy fats or highly processed which promote inflammation7. It’s also common for food sensitivities or intolerances to lead to increased symptoms severity. Common culprits are red meat, nightshades, dairy products, eggs, caffeine, and alcohol.

Getting a handle on how your diet affects your fibromyalgia is a really important part of keeping your symptoms in check.

Can lack of sleep cause a fibromyalgia flare-up?

Poor sleep can exacerbate fibromyalgia symptoms. Sleep disturbances are common in fibromyalgia so you may already be familiar with periods where you are lying awake at night, waking up several times or waking up feeling tired and grumpy. When this happens your body’s pain threshold decreases, fatigue increases, and it may affect your ability to concentrate. Additionally, lack of restorative sleep can disrupt the balance of hormones and neurotransmitters that regulate pain and mood, further contributing to symptom severity.

Does weather cause fibromyalgia flare-ups?

Some individuals with fibromyalgia report that changes in weather, especially cold, damp conditions, can trigger flare-ups. Studies have shown increased pain intensity with decreases in barometric pressure and increases in relative humidity8. While the exact mechanism is not fully understood, it is believed that changes in atmospheric pressure can affect the way the body perceives pain as well as the impact on mood (I mean, when it's cold and grey outside, it can feel a bit the same on the inside!).

Additionally, cold and humid conditions can lead to muscle stiffness and increased pain, while sudden changes in weather can disrupt the body’s homeostasis, leading to increased sensitivity.

Can overdoing it cause my flare-up?

I really only need to look back over my past 30 year history with chronic pain to say that unequivocally yes, pushing through the pain barrier is a sure fire way to cause a flare-up!

Overexertion places the body under stress. It doesn't matter if it is physical or mental overactivity, any kind of additional strain on the muscles and nervous system will lead to increased pain and fatigue. This might include ignoring the timer that suggested taking a break and continuing to work (and this can be chores or at a computer), overcommitting to social events and having a “big weekend” or navigating difficult, painful, or unwanted feelings.

Pacing your activities can help to avoid flares linked to overexertion.

Can exercise cause a flare-up?

While moderate exercise is beneficial for fibromyalgia, excessive or inappropriate exercise can cause flare-ups. Overdoing exercise can strain muscles and joints, leading to increased pain and fatigue. It’s crucial to find the right balance and type of exercise that doesn’t overburden the body, considering the unique sensitivities and limits of individuals with fibromyalgia.

So I just avoid the causes of a fibromyalgia flare?

Sometimes it is not as easy as simply removing a trigger – it might be a situation you can't avoid. I mean you can try praying to the weather Gods or maybe locking yourself in your room to avoid the world around you, but hey, we have to live our lives, right? So feel free to check out some proven strategies for how to recover from a fibromyalgia flare and get yourself prepared. The good news here also is that the more you understand your condition, flare-up triggers and managing your pain in helpful ways, the less frequent and severe our flare-ups will become.

You may have detected a pattern emerging in what causes fibromyalgia to flare up – the causes are unsurprisingly similar to the root causes of fibromyalgia – the complex interaction and sensitivity of the neuro-immuno-endocrine system.  Once these systems get into full swing, become sensitized and overprotective, pain and other symptoms ramp up right alongside it all.

And another overarching culprit of flare-up (as well as a flare-up symptom) is stress. Calm the nervous system, calm the flare-up, or as one of my meditation teachers likes to remind us...'when in doubt, breathe out.'

Help please – a little support here?

When you know what causes flare-ups, you are more likely to be able to avoid or reduce them. By tracking and measuring your response you can be better prepared to minimize or avoid triggers resulting in less flare ups. If you would like to learn more about exploring your fibromyalgia flare-up triggers, our program does just that with supportive coaches, tools and tips for managing your flare-ups.