Why do I get heart palpitations lying down?

The NHS lists the everyday drivers of palpitations - stress and anxiety, caffeine, alcohol, nicotine, some medicines - and notice how many of them cluster in the evening: the wine with dinner, the late coffee, the day's worries finally arriving when you stop moving. Lying down adds its own mechanics. In the daytime, noise, movement, and distraction mask your heartbeat; in a dark, quiet bedroom there is nothing left to compete with it, and a normal 60-beats-a-minute rhythm can sound like a drum. Position amplifies it further: lying on your left side presses the heart closer to the chest wall, so each beat feels stronger, and lying flat shifts blood back toward the chest, making each contraction slightly fuller and more forceful. A heavy late meal and reflux add pounding and fluttering sensations of their own. So the common case is awareness plus posture plus evening stimulants - unsettling, but benign. Still, palpitations are a symptom with a red-flag list, and lying down does not exempt it. Get urgent help if the pounding comes with chest pain, breathlessness, dizziness, or a faint; get a GP appointment if episodes are frequent, last more than a few minutes, or come with a genuinely racing or irregular pulse you can feel at the wrist. Until then: cut late caffeine and alcohol for two weeks, prop yourself slightly, and try the slow-breathing reset - in for four, out for six - which calms the adrenaline loop that sustains many episodes. Pymander is a free AI doctor, 24/7 by text, that can help you work out which pattern fits.