Living with fibromyalgiaoften means that symptoms change from one day to the next. Some days may feel relatively manageable, while others bring a sudden or significant increase in pain, fatigue, sleep problems, brain fog, and other symptoms. These periods of intensified symptoms are commonly known as fibromyalgia flares.

Although flares can be frustrating and disruptive, understanding what they are, recognizing potential triggers, and having a plan for responding can make them feel less overwhelming.

What Is a Fibromyalgia Flare?

A fibromyalgia flare is a period during which fibromyalgia symptoms become noticeably more intense than a person’s usual baseline. A flare may involve worsening widespread pain, muscle stiffness, exhaustion, disrupted sleep, headaches, digestive discomfort, increased sensitivity to light or sound, and difficulty concentrating.

In a qualitative study examining patients’ experiences, people with fibromyalgia described flares as involving increased pain and fatigue, flu-like body aches, exhaustion, and a variety of additional physical and cognitive symptoms. Participants also reported that flares could interfere substantially with work, household responsibilities, relationships, and everyday activities (Vincent et al., 2016).

Flares are not simply an indication that someone is “not trying hard enough” or managing fibromyalgia incorrectly. They reflect the variable nature of a condition associated with changes in how the central nervous system processes painful and nonpainful signals. These changes can increase sensitivity to pain and other sensory input, causing the nervous system to respond more strongly to physical and emotional demands.

What Does a Flare Feel Like?

The experience of a flare differs from person to person. Even within the same individual, one flare may not feel exactly like another. Common symptoms include:

• Increased widespread pain or tenderness

• Greater fatigue or physical exhaustion

• Muscle stiffness and body aches

• Poor or unrefreshing sleep

• Difficulty concentrating or remembering information

• Headaches or migraines

• Digestive symptoms

• Increased sensitivity to noise, light, temperature, or touch

• Feelings of frustration, irritability, anxiety, or discouragement

Research suggests that pain, fatigue, poor sleep, cognitive difficulties, and emotional distress can interact with and reinforce one another. For example, increased pain may disrupt sleep, while poor sleep may further heighten pain sensitivity and fatigue the following day.

What Can Trigger a Fibromyalgia Flare?

Flares do not always have an obvious cause. However, research has identified several commonly reported triggers.

In one prospective study, frequently reported triggers included ongoing stress, periods of intense stress, physical overexertion, and changes in weather. Another study found that people commonly associated flares with stress, doing too much, and poor sleep (Gomez-Arguelles et al., 2022; Vincent et al., 2016).

Potential flare triggers may include:

Physical overexertion

Trying to complete too many activities at once—or significantly increasing activity on a day when symptoms are mild—may result in increased pain and fatigue afterward. This is sometimes called the “boom-and-bust” cycle: a person does as much as possible while feeling better, experiences a symptom increase, and then requires an extended period of recovery.

Emotional stress

Work demands, caregiving responsibilities, relationship difficulties, financial concerns, and major life changes can activate the body’s stress-response systems. Stress does not mean that fibromyalgia is psychological or “all in your head.” Rather, stress can affect nervous-system arousal, muscle tension, sleep, and pain processing, potentially intensifying existing symptoms.

Poor sleep

Sleep disturbances are common in fibromyalgia and may contribute to greater pain, fatigue, and cognitive difficulties. A single night of poor sleep may not cause a flare for everyone, but repeated sleep disruption can reduce the body’s ability to recover from daily demands.

Changes in routine

Travel, disrupted meal schedules, changes in medication, illness, increased work demands, or interruptions in exercise and sleep routines may place additional strain on the body.

Weather changes

Some people report worsening symptoms during changes in temperature, humidity, or barometric pressure. Weather was identified as a commonly perceived trigger in flare studies, although individual responses vary and researchers are still working to understand this relationship.

How Long Does a Fibromyalgia Flare Last?

There is no standard length for a flare. Symptoms may intensify for a few days, several weeks, or longer. The duration often depends on the individual, the circumstances surrounding the flare, the severity of the symptoms, and whether contributing factors such as poor sleep or ongoing stress continue.

Because symptoms can fluctuate for many reasons, it is helpful to pay attention to changes that feel different from a typical flare. New, severe, or unusual symptoms should not automatically be attributed to fibromyalgia and may require medical evaluation.

How to Manage Fibromyalgia Flare-Ups

During a flare, the goal is not necessarily to eliminate every symptom immediately. A more realistic goal is to reduce unnecessary strain, support recovery, and prevent the flare from becoming more disruptive.

Begin by temporarily lowering the demands placed on your body. Prioritize essential responsibilities, postpone nonurgent tasks, and divide necessary activities into smaller steps. Rest can be helpful, but complete inactivity for an extended period may contribute to stiffness, weakness, and greater difficulty returning to normal activity. When tolerated, activities that calm the central nervous systemincluding gentle movement—such as brief walking, stretching, or range-of-motion exercises—may help maintain mobility without overwhelming the nervous system.

Protecting sleep, eating regularly, staying hydrated, using relaxation skills, and following the treatment plan developed with your healthcare providers may also help. Cognitive behavioral therapy, meditative approaches, appropriately paced exercise, and individualized medication management are commonly included within comprehensive fibromyalgia treatment. Current guidelines generally support a multidisciplinary approach rather than relying on a single treatment.

It may also be helpful to respond to yourself with compassion rather than criticism. A flare is not a personal failure. Adjusting your activities is a practical symptom-management strategy, not a sign of weakness.

Can Flares Be Prevented?

Not every flare can be prevented. However, recognizing personal patterns may reduce their frequency or severity.

Consider keeping a simple symptom record that tracks:

• Sleep quality

• Stress levels

• Physical activity

• Pain and fatigue

• Major schedule changes

• Illness or medication changes

• Menstrual or hormonal changes

• Possible environmental triggers

The purpose of tracking is not to monitor every symptom obsessively. Instead, look for broad and repeated patterns. You may discover, for example, that symptoms tend to intensify after several nights of poor sleep or when physically demanding activities are scheduled on consecutive days.

Pacing is another important strategy. Pacing involves balancing activity and recovery before symptoms become overwhelming. Rather than waiting until pain or exhaustion forces you to stop, plan brief breaks, alternate demanding tasks with lighter ones, and increase activity gradually. Exercise recommendations for fibromyalgia typically emphasize beginning at a low level and progressing slowly according to individual tolerance.

When Should You Contact a Healthcare Provider?

Contact a qualified healthcare provider when:

• Symptoms are new, severe, or significantly different from your usual flares

• Pain follows an injury or accident

• You experience fever, unexplained weight loss, significant weakness, chest pain, shortness of breath, or other concerning symptoms

• A flare does not improve or continues to worsen

• Medication is causing side effects or is no longer helping

• Symptoms are interfering substantially with sleep, work, relationships, or daily functioning

• Anxiety, depression, or feelings of hopelessness are becoming difficult to manage

Fibromyalgia can coexist with other medical conditions. A change in symptoms deserves appropriate attention rather than automatically being dismissed as “just fibromyalgia.”

Moving Through a Flare

Fibromyalgia flares can be physically and emotionally exhausting. However, a flare does not erase the progress you have made, nor does it necessarily mean that your condition is permanently worsening.

Learning your triggers, pacing activities, protecting sleep, managing stress, and developing a personalized flare plan can help you respond with greater confidence. Comprehensive treatment may not prevent every difficult day, but it can provide practical tools for reducing symptom burden, improving functioning, and regaining a greater sense of control.

Key Takeaways

• Fibromyalgia flares are temporary increases in symptoms.

• Flares are not a personal failure.

• Triggers vary from person to person.

• Managing a flare requires balance.

• Tracking patterns can improve self-management.

References

Gomez-Arguelles, J. M., et al. (2022). Characterizing fibromyalgia flares: A prospective study. Journal of Clinical Medicine, 11(18), 5448.

Jones, E. A., et al. (2024). Management of fibromyalgia: An update. Biomedicines, 12(6), 1269.

Macfarlane, G. J., et al. (2017). EULAR revised recommendations for the management of fibromyalgia. Annals of the Rheumatic Diseases, 76(2), 318–328.

Vincent, A., Whipple, M. O., McAllister, S. J., Aleman, K. M., & St Sauver, J. L. (2016). Fibromyalgia flares: A qualitative analysis. Pain Medicine, 17(3), 463–468.

Winslow, B. T., Vandal, C., & Dang, L. (2023). Fibromyalgia: Diagnosis and management. American Family Physician, 107(2), 137–144.

Considering treatment for fibromyalgia? At McLean Health Psychology Specialists, we provide individual, evidence-based care for adults living with fibromyalgia, chronic pain, and complex medical conditions. If you're ready to work with a clinician who specializes in the unique challenges of fibromyalgia, we invite you to schedule a consultationand learn how health psychology can support your treatment journey.

Learn more about our fibromyalgia treatment program.

About the Author

This article was written by Catherine DeBoer, PsyD, ABPP, a Board-Certified Clinical Health Psychologist and fibromyalgia treatment specialist located in McLean, VA. The information provided is based on current scientific research and clinical expertise and is intended for educational purposes only. It should not be considered a substitute for personalized medical advice, diagnosis, or treatment.

© 2026 Catherine DeBoer, PsyD, ABPP. All rights reserved. No portion of this publication may be reproduced, distributed, or transmitted in any form or by any means without prior written permission, except for brief quotations used for educational or scholarly purposes with appropriate attribution.