Fibromyalgia is a chronic pain condition defined by widespread musculoskeletal pain, often accompanied by severe fatigue, non-restorative sleep, and cognitive difficulties, sometimes called “fibro fog.” The condition is understood as a disorder of pain processing, where the central nervous system amplifies pain signals, a process known as central sensitization. While not traditionally considered a respiratory disease, many people living with this condition report a persistent dry cough, leading to questions about a direct connection. This common symptom is typically explained not by the fibromyalgia itself, but by frequently co-occurring conditions or necessary treatments.
Assessing the Direct Connection to Fibromyalgia
Fibromyalgia is primarily a neurological disorder affecting how the brain and spinal cord process sensation. The core pathology involves heightened sensitivity throughout the nervous system, not inflammation or structural changes in the lungs or airways that would inherently cause a cough. A chronic dry cough is a reflex response designed to clear the respiratory tract, a function separate from the generalized pain of fibromyalgia.
The concept of centralized sensitivity may offer a theoretical, secondary explanation for a cough. People with fibromyalgia often experience generalized hypersensitivity, which might extend to the vagus nerve, mediating the cough reflex. This could make the throat or airways overly responsive to minor irritations, causing a chronic dry cough due to a lower threshold for irritation. However, this is not a recognized direct cause of the condition itself, and the cough usually points to another underlying factor.
Common Co-occurring Conditions That Cause Cough
The most frequent explanation for a chronic dry cough involves co-occurring conditions that affect the upper digestive or nervous systems. Gastroesophageal Reflux Disease (GERD) is highly prevalent in people with fibromyalgia. GERD and its variant, Laryngopharyngeal Reflux (LPR), occur when stomach acid or digestive enzymes travel up the esophagus, irritating the throat and vocal cords. This irritation triggers a chronic dry cough, which often worsens when lying down, particularly at night.
The generalized hypersensitivity seen in fibromyalgia often extends to the gastrointestinal tract, manifesting as Irritable Bowel Syndrome (IBS). This visceral hypersensitivity may increase the likelihood of reflux symptoms, even without the typical heartburn sensation, a scenario known as “silent reflux.” Another frequently co-occurring issue is dysautonomia, a dysfunction of the autonomic nervous system. Since the vagus nerve mediates the cough reflex, this dysregulation could contribute to an irritative cough or throat clearing, though less often than reflux.
Medications Used in Treatment That Cause Dry Cough
Medications used to manage fibromyalgia and its associated conditions are a common cause of a persistent dry cough. Patients may be prescribed drugs like Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs) or Gabapentinoids to help with pain and fatigue. While dry mouth is a common side effect, some neurological medications can cause respiratory or mucosal symptoms, including a dry cough.
A more prominent cause of a chronic dry cough is often found in medications treating comorbidities. Many people with fibromyalgia manage conditions like hypertension or migraines and may be prescribed an Angiotensin-Converting Enzyme (ACE) inhibitor. This class of drug is well-known to cause a non-productive, persistent cough in a significant percentage of users. The cough typically resolves upon discontinuing the medication, so patients should review their full medication list with a physician to determine if an ACE inhibitor or another drug is the source of the irritation.
When to Seek Medical Consultation
Any cough that persists for eight weeks or longer should be evaluated by a healthcare provider, as it meets the definition of a chronic cough. For someone with fibromyalgia, a physician must differentiate between an irritating cough caused by reflux or medication and symptoms indicating a more serious, unrelated problem. A differential diagnosis is necessary to rule out non-fibromyalgia-related causes, such as asthma, postnasal drip, or environmental irritants.
Immediate medical attention is necessary if the dry cough is accompanied by warning signs such as coughing up blood, unexplained weight loss, fever, or difficulty breathing. To help the physician determine the cause, maintaining a symptom diary is beneficial. This diary should note when the cough occurs, its relation to meals, and whether it started after a change in medication, aiding in identifying the source of the irritation.