Why do I get dizzy from standing too long?

Standing still is harder on your circulation than it looks. When you stand, gravity pulls blood downward, and your body normally counters it with movement - calf muscles squeezing veins like pumps with every step and shift. Stand motionless for twenty minutes at a concert, in a queue, or at a kitchen counter, and that pump idles: blood pools in the legs, less returns to the heart, blood pressure drifts down, and the brain - last in the queue - announces the shortfall as light-headedness, tunnel-vision edges, and that floaty feeling. This is the same vasovagal pathway behind standing-related faints, and it has known amplifiers: heat (hot venues and summer queues dilate vessels), dehydration, hunger, illness, and standing up again quickly after sitting. The counter-moves are physical and instant: keep the calf pump running - shift your weight, rock on your heels, march in place, or cross your legs and squeeze your thighs and buttocks together, which pushes pooled blood back up within seconds. At the first wave of dizziness, sit down or lie down with your legs raised; do not try to tough it out, because the next stage is the floor. Hydrate and eat before long standing events. Most standing dizziness is benign, but the fainting red flags matter: a faint that comes with palpitations or chest pain, one with no warning at all, one while lying or sitting, or any injury from a fall deserves a medical review, and repeated near-faints despite these measures warrant a GP visit to check blood pressure, iron, and medicines. Pymander is a free AI doctor, 24/7 by text, that can help you weigh yours.