What to do if…
your smartwatch flags an unusually low heart rate and you feel faint

What to do now

1. Get into a safer position immediately. Lie flat if you can. If you feel you might faint, raise your legs on a sofa, chair, or cushions. Stay still.
2. Call 999 now if you faint, are not fully recovering, or have any of these symptoms: chest pain, shortness of breath, difficulty speaking or moving, a pounding, fluttering, or irregular heartbeat, serious injury from a fall, shaking or jerking, fainting during exercise, or fainting while lying down. If someone with you is not breathing normally, call 999 and start CPR if you know how, or follow the call handler’s instructions.
3. If you call 999, say clearly: “My smartwatch showed an unusually low heart rate and I feel faint.” Tell them your location, whether you have fainted, whether you are breathing normally, and whether you have chest pain, breathing difficulty, or an irregular heartbeat.
4. If you are not calling 999, get another person involved now. Ask someone nearby to stay with you, or call someone and keep them on the phone. If you are alone at home, unlock the door if you can do that without standing or worsening your symptoms.
5. Do one calm check without standing up. If you can, feel your pulse at your wrist for about 30 seconds and note whether it feels very slow, irregular, or hard to find. Stop checking if it makes you more anxious or you feel worse.
6. If you are safely seated or lying down, note anything obvious about the watch reading, such as whether the watch was loose, had moved, or gave repeated very low readings. Do not use a better later reading as a reason to ignore ongoing faintness.
7. Keep useful details ready for the clinician or call handler: the watch reading, the time it happened, what you were doing, whether you actually fainted, any chest pain or breathlessness, and any recent changes to heart, blood pressure, or rhythm medicines.
8. If the faint feeling settles and none of the 999 triggers apply, get same-day urgent medical advice. In England, use NHS 111 online if suitable or call 111. Elsewhere in the UK, use your local NHS urgent-help route from the NHS 111 guidance page. If symptoms return or worsen, switch to 999.