Fibromyalgia is a chronic disorder that causes widespread musculoskeletal pain, fatigue, sleep problems, and emotional distress. People with fibromyalgia often experience an increased sensitivity to pain, making even mild discomfort feel more intense.

This condition affects about four million adults in the United States, or roughly 2% of the adult population. Although the exact cause is unknown, fibromyalgia can be effectively managed with the right treatment and lifestyle changes.

While fibromyalgia is not an autoimmune disease, its symptoms can resemble those of autoimmune disorders. It also tends to overlap with several other health conditions — sometimes in surprising ways.

Below are seven conditions commonly linked to fibromyalgia and how they interact.

Chronic Migraine

a shared neurological connection
Fibromyalgia and chronic migraine are strongly connected, with each condition increasing the risk of the other over time. Research shows they share a bidirectional relationship, meaning either can trigger or worsen the other.

The connection may stem from imbalances in brain chemicals such as serotonin and norepinephrine, which regulate both pain and mood. When these chemical messengers are disrupted, pain signals become amplified, contributing to both fibromyalgia and migraines.

managing migraines:
Antidepressant medications that target serotonin and norepinephrine can help relieve migraine pain. Some people also benefit from biofeedback therapy, a technique that helps you gain control over certain body functions — like heart rate or muscle tension — to reduce stress and pain.

Autoimmune Diseases

how inflammation overlaps with fibromyalgia
Although fibromyalgia isn’t an autoimmune disorder, it frequently coexists with inflammatory autoimmune diseases such as:

  • Rheumatoid arthritis (RA)

  • Lupus

  • Sjögren’s syndrome

  • Ankylosing spondylitis

People with RA or similar inflammatory conditions have a higher risk of developing fibromyalgia. However, unlike autoimmune diseases, fibromyalgia stems from abnormal pain processing in the central nervous system, not immune system inflammation.

Sleep Problems

when pain disrupts rest
Nearly 90% of people with fibromyalgia experience sleep difficulties. Pain and discomfort make it hard to fall asleep or stay asleep, leading to poor rest quality and daytime fatigue.

According to experts, lack of restorative sleep can worsen fibromyalgia symptoms, creating a cycle of pain and exhaustion. Over time, this can lower energy, mood, and overall quality of life.

Improving sleep hygiene — such as keeping a consistent bedtime, limiting screen time before sleep, and managing pain effectively — can significantly help.

Restless Leg Syndrome (RLS)

the urge to move and sleepless nights
Restless leg syndrome causes an uncontrollable urge to move the legs during rest, making it difficult to sleep. Studies show that up to 37% of people with RLS also have fibromyalgia.

This overlap may stem from shared disruptions in brain signaling or dopamine function. Treating fibromyalgia can often lessen RLS symptoms, leading to improved sleep and reduced fatigue.

Irritable Bowel Syndrome (IBS)

the gut–pain connection
Fibromyalgia and irritable bowel syndrome (IBS) often occur together, with each condition capable of triggering or worsening the other. IBS causes abdominal cramps, bloating, constipation, and diarrhea.

A 2017 study found that people with fibromyalgia were 1.5 times more likely to develop IBS compared to those without it. Both conditions are linked to nervous system hypersensitivity and stress-related changes in gut-brain communication.

Managing diet, staying hydrated, and reducing stress can help control IBS symptoms and lessen overall pain.

Pelvic Pain

a hidden musculoskeletal symptom
Fibromyalgia can also cause chronic pelvic pain, especially in women. Research has shown that people with severe fibromyalgia often experience more intense pelvic discomfort, menstrual cramps, and bladder irritability.

Medications that relieve fibromyalgia symptoms — such as nerve pain regulators and antidepressants — can also help ease pelvic pain.

Depression and Anxiety

the emotional side of fibromyalgia
More than half of people with fibromyalgia experience mental health conditions like depression or anxiety. In some studies, up to 97% of individuals with fibromyalgia also had at least one co-occurring mental disorder.

Experts believe both fibromyalgia and mood disorders share common causes — such as low serotonin and norepinephrine levels. These chemical imbalances can influence both pain sensitivity and emotional regulation.

This explains why several fibromyalgia medications are also antidepressants — helping reduce both physical and emotional symptoms simultaneously.

Obesity

a cycle of inactivity and pain
Chronic pain often leads to a sedentary lifestyle, which increases the risk of weight gain and obesity. Excess weight puts more strain on the joints and can worsen fibromyalgia pain.

As psychiatrist Dr. Lesley Arnold explains, “Being overweight places more mechanical stress on your joints, which can cause more pain and aggravate fibromyalgia.”

The good news: research shows that even low-intensity physical activity, like walking or gentle stretching, can reduce pain, fatigue, and anxiety. Regular movement also supports better sleep and mood — key elements in fibromyalgia management.

A Quick Review

Fibromyalgia affects millions of people and often overlaps with other health conditions — including migraines, autoimmune diseases, sleep disorders, RLS, IBS, pelvic pain, depression, and obesity.

While the cause remains unclear, treatment focuses on improving sleep, managing stress, reducing inflammation, and maintaining gentle physical activity. With a comprehensive care plan, many people can find meaningful relief and a better quality of life.