A head rush, or orthostatic hypotension, is caused by a sudden drop in blood pressure. This condition is more common in people over the age of 65 but can occur at any age. Orthostatic hypotension affects between 5 and 20 percent of the population.1
Orthostatic hypotension can occur after eating or standing and can be with or without symptoms. The symptoms are usually temporary and include lightheadedness, dizziness, fainting, and muscle aches.
Most people have an occasional episode of dizziness when standing, especially if they have a viral infection, dehydration, or are on prolonged bed rest. If your symptoms are chronic or occur repeatedly, it may indicate another health problem, which should be investigated by your doctor.
When you stand up suddenly, your body needs to compensate quickly for a sudden drop in blood pressure in the upper body.2
If your blood vessels do not constrict fast enough to maintain your blood pressure, it drops too much. For most people, standing causes a decrease in blood pressure of 5 to 10 mm Hg and an increase in their pulse by 10 to 25 beats per minute.
In people with orthostatic hypotension, systolic blood pressure drops at least 20 mm Hg (millimeters of mercury), and diastolic blood pressure drops at least 10 mm Hg. This is because their nervous system does not respond quickly enough. This can cause the symptoms, referred to as a head rush. However, it is a bit of a misnomer in that it is a decrease in blood flow to the head, not an increase that is causing symptoms.
The drop in blood pressure can cause the following symptoms due to decreased blood flow into the brain:
Orthostatic hypotension is more common in older adults. This is likely due to decreases baroreceptor sensitivity and slow compensation to changes in blood pressure.
The most common cause of chronic dizziness with position changes is decreased baroreceptor sensitivity. This is most common in older adults, but can occur at any age.
Neurologic conditions can also cause chronic dizziness. Examples include:
A decrease in blood volume can decrease blood pressure and cause dizziness and lightheadedness. Common causes include:
All drugs have side effects. Sometimes the beneficial effect of the medication can also cause side effects. For example, weight loss medications typically do not decrease blood pressure, but weight loss can. Some people may notice increased dizziness when standing, when dieting, or after weight loss.
Several drugs cause a decrease in blood pressure as a primary response or a side effect, including the following:3
These conditions may coexist with orthostatic hypotension because they cause similar symptoms, have a similar physiologic cause, or are side effects of medications.
Postural orthostatic tachycardia (POTS) syndrome is like orthostatic hypotension in that changes in body position cause an increase in heart rate, which causes symptoms. The symptoms are almost identical to those associated with orthostatic hypotension, and the lifestyle management suggestions are as well. POTS is diagnosed when you have symptoms that occur when standing upright, but orthostatic hypotension and dehydration have been ruled out as a cause.
Diabetes is a risk factor for orthostatic hypotension, which can cause dizziness. But dizziness and lightheadedness are not typically associated with type 2 diabetes.
Low blood sugar, or hypoglycemia, can also cause dizziness, sweating, and fainting. Symptomatic hypoglycemia is more common in type 1 diabetes but can be a medication side effect in type 2 diabetes.
Chronic dizziness is a nonspecific symptom that may have multiple causes, some serious. If you have dizziness or lightheadedness, it could be a benign condition, or it may be an inner ear or heart problem.
If you have confusion or brain fog, it may be due to vitamin B12 deficiency or a neurologic condition.
If you faint or lose consciousness when standing, it may be due to an undiagnosed heart condition.
Isolated dizziness and lightheadedness when going from sitting to standing are common, but if your symptoms persist or get worse, talk with your doctor.
If you have drops in your blood pressure when standing, slowly change position to give your body time to adjust.
These lifestyle modifications can also reduce your symptoms:
Vitamin B12 deficiency is a known cause of neuropathies. These changes in nerve function can increase orthostatic hypertension and other neurologic conditions. Ask your doctor if vitamin B12 deficiency may be contributing to your symptoms.
Age is a risk factor for orthostatic hypotension, and dizziness when standing increases your risk for falls. Maintaining good muscle tone in your legs and developing a good sense of balance are great age management techniques that can decrease your risk and symptoms.
There are many potential causes of chronic dizziness. If you are uncertain about what is causing your symptoms or if they persist, see your doctor.
While we strive to always provide accurate, current, and safe advice in all of our articles and guides, it’s important to stress that they are no substitute for medical advice from a doctor or healthcare provider. You should always consult a practicing professional who can diagnose your specific case. The content we’ve included in this guide is merely meant to be informational and does not constitute medical advice.