Heart palpitations only at night: what to know

With fewer daytime distractions, a normal heartbeat can feel unusually forceful, fast or irregular. Caffeine, nicotine, alcohol, heavy meals, fever, poor sleep, emotional strain and dehydration can all make the sensation more likely. Lying down may also make movement in the chest easier to feel.

A clinician may consider anaemia, iron deficiency anaemia, an overactive thyroid, low blood sugar, or an electrical rhythm such as atrial fibrillation. A night-time pattern does not identify the cause by itself. Note whether the beat feels regular or chaotic, how long it lasts, and whether it starts or stops suddenly.

Keep a brief record of the time, activity, food or drink beforehand, sleep quality, medicines and accompanying symptoms. Reduce evening caffeine and nicotine, avoid alcohol close to bedtime, drink fluids regularly, and use slow breathing if worry amplifies the sensation. Do not stop prescribed medicine without advice.

Arrange a routine appointment if episodes recur, disturb sleep, or come with fatigue, breathlessness or dizziness. Assessment may include an examination, an ECG and blood tests; a portable monitor can capture an episode that does not occur during the visit.

Seek emergency help for palpitations with chest pressure or pain, severe breathlessness, fainting, new confusion, or marked weakness. Get prompt medical advice for a sustained rapid or irregular heartbeat, especially if you have known heart disease or symptoms of heart failure such as breathlessness when lying flat and new leg swelling.

Ask whether your pattern calls for an ECG or wearable rhythm monitor, whether blood tests should check thyroid function, blood count or glucose, and which medicines or supplements could contribute. Mention snoring, disrupted sleep, pregnancy, recent illness and every stimulant you use.