Symptoms Of Postprandial HypotensionPeople who have postprandial hypotension will often notice lightheadedness, dizziness, weakness or even syncope (loss of consciousness) when they stand up within 30 to 60 minutes after eating a meal. Symptoms tend to be more severe after eating a large meal or a meal that includes a lot of carbohydrates, or if alcohol has recently been consumed.
What Causes Postprandial Hypotension?The cause of postprandial hypotension is not completely understood. It is thought that the condition is caused by a pooling of blood in the abdominal organs during the process of digestion. Because of this blood pooling, the amount of blood available to the general circulation drops, causing the blood pressure to fall when standing upright.
Some amount of blood pooling in the abdominal organs after a meal is normal. In people with postprandial hypotension, however, it is thought that this blood pooling is exaggerated or that the normal reflex that constricts the blood vessels in the legs (to compensate for pooling) is diminished.
Eating high-carbohydrate meals appears to worsen postprandial hypotension. This fact has led some investigators to theorize that in people who have this condition, insulin or other blood chemicals that are released in response to eating carbohydrates may abnormally increase the dilation of the abdominal blood vessels after a high-carb meal.
To some extent, aging is accompanied by an increase in the abdominal blood pooling that normally occurs after a meal. Most older people never develop symptoms from such increased blood pooling - but people who do tend to be elderly.
Treating Postprandial HypotensionWhile there is no specific treatment to eliminate postprandial hypotension, symptoms can be controlled adequately in the large majority of people who have this condition.
Treating symptoms involves four elements:
- Eat smaller, more frequent meals. Eating large meals tends to exaggerate abdominal blood pooling. Smaller meals mean less blood pooling.
- Avoid high-carbohydrate meals.
- Avoid alcohol. Alcohol relaxes blood vessels and tends to prevent the constriction of blood vessels in the legs that would normally compensate for abdominal blood pooling.
- Stay seated for 30 to 60 minutes after eating. The abdominal blood pooling tends to dissipate within an hour or so after a meal.
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