# Palpitations

URL: https://thethyroidologist.com/symptoms/palpitations/
Section: Symptoms
Last medically reviewed: 2025-11-01

> A racing or irregular heartbeat can be caused by hyperthyroidism — but also anxiety, caffeine, arrhythmias. When thyroid testing is worthwhile.

Palpitations — the sensation of a racing, pounding or irregular heartbeat — are common and have many causes. Thyroid overactivity is a recognised contributor, but anxiety, caffeine, and heart rhythm problems are equally or more common.
This page helps distinguish when thyroid evaluation is appropriate.

## Thyroid connection

Hyperthyroidism increases heart rate and contractility — thyroid hormone directly stimulates the heart. Patients often notice resting tachycardia, palpitations on exertion, or an irregular pulse.
Atrial fibrillation — an irregular, often rapid heart rhythm — is a recognised complication of hyperthyroidism, particularly in older patients.

## Other causes

Anxiety and panic attacks, caffeine and stimulants, nicotine, anaemia, low blood sugar, dehydration, electrolyte imbalance, and primary arrhythmias (SVT, atrial fibrillation, premature beats) all cause palpitations.
In many cases, palpitations are benign — but new or persistent palpitations deserve evaluation.

## Evaluation

Thyroid testing (TSH, free T4) is appropriate when palpitations accompany hyperthyroid features — weight loss, heat intolerance, tremor — or occur with an irregular pulse on examination.
An ECG is often the first test; ambulatory monitoring (Holter) may be needed for intermittent symptoms. If thyroid tests are normal, cardiac evaluation continues.

## Frequently asked questions

### Can hypothyroidism cause palpitations?

Rarely — hypothyroidism typically slows the heart. However, palpitations can occur if hypothyroidism coexists with other causes or if medication dose is excessive.

### Is atrial fibrillation from thyroid reversible?

Often yes — treating the underlying hyperthyroidism can restore normal rhythm, though some patients have persistent AF needing ongoing management.

### When are palpitations an emergency?

Palpitations with chest pain, severe breathlessness, fainting, or a sustained very rapid irregular pulse need urgent assessment.

## Disclaimer

The content on this website is for general educational purposes only and does not constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional about your specific condition.

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Part of The Thyroidologist — https://thethyroidologist.com