What should you know about caffeine heart palpitations at night?

Palpitations are an awareness of pounding, fluttering, racing or skipped beats. Caffeine may increase alertness and make ordinary beats easier to feel when the room is quiet. A late drink can also reduce sleep and increase anxious sensations. Dehydration, low blood sugar, anaemia, iron deficiency anaemia or an overactive thyroid can contribute to a racing heartbeat.

Palpitations do not by themselves identify atrial fibrillation or heart failure. A clinician may need to examine you and record the rhythm while symptoms are present.

Sit comfortably, breathe slowly, and avoid more caffeine, nicotine, alcohol and intense exertion while symptoms continue. Drink water if you may be dehydrated. Write down the start time, duration, regularity, preceding drink, medicines and associated symptoms. Do not stop prescribed heart medicine without advice. A gradual caffeine reduction may help if episodes follow late or strong drinks.

Call emergency services for palpitations with chest pain, severe breathlessness, fainting, collapse, confusion or new weakness. Seek prompt medical advice if the rhythm remains very fast or irregular, episodes recur, or you have known heart disease. Assessment may include an ECG, blood tests and a monitor worn outside the clinic.

Could caffeine, thyroid function, anaemia or dehydration explain this? Should I have an ECG or rhythm monitor? Which symptoms should send me to emergency care?