Can hyperthyroidism (an overactive thyroid gland) cause vertigo?

Can Hyperthyroidism Cause Vertigo?

Hyperthyroidism itself is not a recognized direct cause of vertigo, but vertigo is listed as an adverse reaction to propylthiouracil (an antithyroid medication used to treat hyperthyroidism), and there is emerging evidence linking autoimmune thyroid disease—particularly Hashimoto's thyroiditis—to vestibular dysfunction. 1

Direct Relationship Between Hyperthyroidism and Vertigo

The major clinical guidelines and FDA drug labels do not list vertigo as a primary symptom of hyperthyroidism:

• Common symptoms of hyperthyroidism include tremors, nervousness, insomnia, excessive sweating, heat intolerance, tachycardia, hypertension, anxiety, palpitations, unintentional weight loss, and diarrhea—but vertigo is notably absent from this list 2, 3

• Cardiovascular manifestations dominate the clinical picture, with increased heart rate, cardiac output, atrial arrhythmias, and potential heart failure in severe cases, but vestibular symptoms are not mentioned 2

• Neuropsychiatric symptoms reported in subclinical hyperthyroidism include systemic complaints, but vertigo is not specifically identified 2

Medication-Related Vertigo

Propylthiouracil (PTU), an antithyroid drug used to treat hyperthyroidism, lists vertigo as a reported adverse reaction 1. This is an important clinical pitfall: if a patient with hyperthyroidism develops vertigo after starting PTU, consider medication-related etiology rather than the thyroid disease itself.

Autoimmune Thyroid Disease and Vestibular Dysfunction

The relationship becomes more complex when considering autoimmune thyroid disease:

• Hashimoto's thyroiditis (autoimmune hypothyroidism, not hyperthyroidism) has been associated with vestibular disorders in well-designed prospective studies 4

• Patients with Ménière disease had significantly higher prevalence of positive anti-thyroid autoantibodies compared to healthy controls, with more than half having either anti-thyroid or non-organ-specific autoantibodies 4

• Benign paroxysmal positional vertigo (BPPV) patients had significantly higher serum TSH and antithyroid autoantibody levels than controls, with almost one-fifth of euthyroid patients with Hashimoto's showing signs of BPPV 4

• Hypothyroidism with Hashimoto's thyroiditis was associated with increased BPPV recurrence risk, particularly in patients with positive thyroid antibodies (TPO-Ab and TG-Ab) 5

Clinical Algorithm for Evaluation

When a patient with hyperthyroidism presents with vertigo:

1. Review medication history: Check if the patient is taking propylthiouracil, as vertigo is a known adverse reaction 1

2. Assess thyroid antibody status: Order anti-thyroid peroxidase (TPO-Ab) and anti-thyroglobulin (TG-Ab) antibodies to evaluate for concurrent autoimmune thyroid disease 4

3. Consider alternative diagnoses: Evaluate for BPPV, Ménière disease, or other vestibular pathology, as these may coexist with autoimmune thyroid conditions 4

4. Rule out cardiac causes: Given that hyperthyroidism causes tachycardia and arrhythmias, ensure vertigo is not secondary to cardiac dysfunction or atrial fibrillation 2

Critical Clinical Pitfalls

• Do not assume vertigo is from hyperthyroidism itself—the evidence does not support this direct relationship 2, 3

• Do not overlook medication side effects—propylthiouracil can cause vertigo independent of thyroid status 1

• Do not miss coexisting autoimmune conditions—patients with Graves disease (the most common cause of hyperthyroidism) may have other autoimmune disorders affecting the vestibular system 4

• Do not delay ENT evaluation—if vertigo persists despite thyroid normalization, pursue dedicated vestibular assessment as the vertigo likely has a separate etiology 6, 4