Fibromyalgia is a chronic condition characterized by widespread pain, fatigue, sleep disturbances, and cognitive challenges. Hives (urticaria) are a common skin reaction appearing as itchy, raised welts that vary in size and shape. This article explores the relationship between these two conditions, addressing whether one causes the other and discussing common co-occurrences.
Is There a Direct Link?
Current medical understanding does not indicate that fibromyalgia directly causes hives. While both conditions are chronic, one does not directly lead to the other. Itching is relatively uncommon as a direct symptom of fibromyalgia itself; only a small percentage of individuals with fibromyalgia reported unexplained itching in one study.
Fibromyalgia involves altered nerve pathways, leading to increased sensitivity to pain, touch, and other sensations. This heightened sensitivity might explain why some individuals with fibromyalgia experience various skin issues or discomforts, including itchiness. Pain and itch sensations share common pathways in the spinal cord and activate similar brain areas, suggesting a sensitivity to pain might correlate with a sensitivity to itchiness. Although the American College of Rheumatology included rashes as a possible symptom in its 2010 diagnostic criteria for fibromyalgia, a rash alone is not sufficient for a diagnosis.
Associated Conditions and Triggers
Individuals with fibromyalgia may experience hives due to various indirect factors, including shared underlying mechanisms, co-occurring conditions, or external triggers.
Mast Cell Activation Syndrome (MCAS)
Mast Cell Activation Syndrome (MCAS) is a condition where mast cells, a type of immune cell, become overactive and release excessive inflammatory mediators like histamine. This overactivity can lead to symptoms like itching, flushing, and hives. Mast cells are present throughout the body, including the skin, and their dysregulation can have widespread effects. Research indicates that chronic urticaria, which involves mast cell stimulation, is more common in individuals with fibromyalgia. Some studies also suggest an increased number of mast cells in the skin tissues of those with fibromyalgia.
Chronic Stress
Chronic stress, often prevalent in individuals managing fibromyalgia, can act as a trigger for hives. Emotional stress can exacerbate or initiate skin reactions by influencing the immune and nervous systems. Stress has been identified as a factor in mast cell activation. The severity of both fibromyalgia and urticaria can also be heightened by anxiety and sleep disturbances.
Medications
Certain medications prescribed for fibromyalgia symptoms can cause hives as a side effect. Examples include pain relievers like ibuprofen and naproxen, and antidepressants such as duloxetine and milnacipran. Anti-seizure medications like pregabalin, sometimes used for fibromyalgia, have also been reported to cause hives. If new skin reactions, including hives, develop after starting a new medication, consult a healthcare professional.
Autoimmune Conditions
Although fibromyalgia is not classified as an autoimmune disease, it frequently co-occurs with other autoimmune conditions that can directly cause hives. About one in five people with chronic hives also have an autoimmune disease like lupus, rheumatoid arthritis, or thyroid disease. Fibromyalgia can also be present alongside these and other autoimmune disorders.
Increased Sensitivities
Individuals with fibromyalgia often report increased sensitivities, which can extend to skin reactions. This heightened sensitivity may stem from neurotransmitter imbalances, such as serotonin, affecting skin sensitivity and contributing to itchiness. Dysregulation of the autonomic nervous system and neurogenic inflammation, where nerve activity releases chemicals, can also make the skin more prone to itching, redness, and discomfort. Specific skin conditions like dermographism (raised welts from light scratching) and hyperhidrosis (excessive sweating) are more commonly observed in people with fibromyalgia.
When to Consult a Healthcare Professional
Consult a healthcare professional if hives are persistent, severe, or recur frequently. While many cases of hives are mild and resolve on their own, ongoing or disruptive symptoms warrant medical evaluation.
Immediate medical attention is necessary if hives are accompanied by severe symptoms. These include swelling of the face, lips, tongue, or throat, difficulty breathing, wheezing, dizziness, or a racing heart, as these could indicate anaphylaxis. If hives appear after starting a new medication, seek prompt medical advice, as this could signal an allergic reaction. A healthcare professional can help determine the underlying cause of the hives, differentiate between triggers, and recommend appropriate management strategies, which may include antihistamines or other treatments.