Dizziness when standing up is often caused by a sudden drop in blood pressure known as orthostatic hypotension. When you move from lying down or sitting to standing, gravity causes blood to pool in your legs and feet. This pooling reduces the amount of blood returning to your heart and subsequently lowers the blood flow to your brain, leading to feelings of lightheadedness or dizziness. Normally, your body quickly adjusts by narrowing blood vessels and increasing heart rate to maintain blood pressure, but if this adjustment is slow or insufficient, dizziness occurs.
Several factors can contribute to this condition. Dehydration reduces blood volume, making it harder for your body to maintain blood pressure when you stand. Prolonged inactivity, such as lying in bed for a long time, can weaken the responsiveness of your blood vessels. Certain medications, especially those that lower blood pressure or cause fluid loss, can also increase the risk. Age plays a role too, as older adults often have less flexible blood vessels and slower regulatory responses, making them more prone to dizziness upon standing.
Other causes include underlying health conditions like heart problems or nervous system disorders that affect blood pressure regulation. Sometimes, after eating, blood flow is redirected to the stomach and intestines, which can temporarily lower blood pressure and cause dizziness, especially after meals high in refined carbohydrates.
In some cases, dizziness when standing may be related to inner ear problems that affect balance, but the most common cause remains the drop in blood pressure due to blood pooling in the lower body. To reduce dizziness, it helps to stand up slowly, stay hydrated, avoid prolonged sitting or standing, and review medications with a healthcare provider if dizziness is frequent or severe.
Sources
https://timesofindia.indiatimes.com/life-style/health-fitness/health-news/why-you-feel-dizzy-when-you-stand-up-the-surprising-causes-of-morning-wooziness-and-how-to-stop-it/articleshow/124508356.cms
https://www.droracle.ai/articles/457667/dizziness-with-standing
https://drlesliekoh.com.sg/blog/feeling-dizzy-after-standing-up-ent-vs-other-causes/
https://my.clevelandclinic.org/health/diseases/orthostatic-intolerance
http://hhccenterforhealthyaging.org/health-wellness/health-resources/health-library/detail?id=dizzi&lang=en-us
https://drrodolico.com/blogs/health-blog/postural-hypotension-dizziness-standing
https://www.apollo247.com/health-topics/dizziness/dizziness-causes-guide
