Rule out medically, first

Palpitations need a medical assessment **before** any psychological explanation — not as a formality. Common, treatable causes: **hyperthyroidism** (adds weight loss, heat intolerance, tremor), **anaemia**, **dehydration**, rhythm disorders such as atrial fibrillation or supraventricular tachycardia, and **hypoglycaemia**. Caffeine, nicotine, nasal decongestants, thyroid hormones and some asthma inhalers produce exactly the same effect. An ECG, a full blood count and thyroid tests are the reasonable minimum. Anxiety is offered as the explanation **after** those come back clear, not instead of them.

What is actually happening

The sympathetic nervous system speeds the heart as part of the fight-or-flight response. It doesn't need a real danger — a thought, a bodily sensation, or simply accumulated background activation is enough.

Here is where the loop that turns an episode into a problem starts. You notice the beats. Noticing produces worry. Worry releases adrenaline. Adrenaline speeds the heart further. You now have evidence that "something is happening", and the cycle tightens.

The phenomenon is called interoceptive sensitivity: the more closely you monitor a bodily signal, the more strongly you perceive it. Your heart beats like everyone else's; the difference is how loudly you hear it.

What it could be

Several possibilities, because this list is not a diagnosis. What separates them is in the detail below each.

Panic attack
How to tell
Comes on abruptly, peaks in under 10 minutes, with a clear sense of impending death, tingling and dizziness. It ends on its own. The ECG at A&E is normal — a result that repeats and doesn't reassure.
Background anxiety
How to tell
Not episodic but a slightly raised pulse nearly all the time, most noticeable in the evening and in quiet. Often accompanied by muscle tension and light sleep.
Bodily hypervigilance
How to tell
The pulse is objectively normal but you hear it constantly. Frequently follows a frightening episode or an illness in the family. Here the problem isn't the heart, it's the attention — and it is treated as such.
Withdrawal or stimulants
How to tell
Appears the day after alcohol, on abruptly cutting caffeine, or 30-60 minutes after coffee, energy drinks or nicotine. The pattern tracks the clock rather than your thoughts — easiest to spot with a log.

What helps now

Don't take your pulse. It's the most counterintuitive item here and the most effective. Repeated checking is what maintains the sensitivity; each measurement brings calm for a few minutes and strengthens the loop.

Breathe out longer than in. Four seconds in, six to eight out, for two minutes. A prolonged exhale activates the vagus nerve and lowers heart rate — one of the few techniques that acts directly on physiology.

Cold on the face. Triggers the diving reflex, which slows the pulse within seconds.

Cut caffeine for two weeks, as a test. Not permanently — as an experiment with an interpretable result.

Move. Counterintuitive when you fear your heart, but regular aerobic exercise lowers resting heart rate and, just as importantly, re-teaches you that a raised pulse is safe.

When to get help

**Go to A&E now if the palpitations come with chest pain, breathlessness, fainting, or pain radiating into the arm or jaw — call 112.** Book an appointment if episodes last more than a few minutes, if the pulse is irregular, if they appear on exertion, or if you have a family cardiac history. Once the medical work-up is clear and the episodes continue, a psychological assessment is the logical next step — not a consolation prize.