Ever stood up too quickly and suddenly felt so dizzy you had to grab a wall or sit right back down? 

It's actually pretty common to feel some brief dizziness when standing up. This sensation is generally caused by orthostatic or postural hypotension, a specific type of low blood pressure that relates to a change in your posture. 

But dizziness that persists for longer than a few seconds could be a sign of something more serious, says Dr. Harikiran Chekuri, medical Head at ClinicSpots Holistic Healthcare. 

Dizziness when standing can affect anyone, but it's most common in people over the age of 65, since blood vessels weaken as you age. 

Weaker blood vessels mean your brain cells don't get enough oxygen, which can lead to lightheadedness and fainting spells, says Nancy Mitchell, registered nurse and contributing writer for AssistedLivingCenter.com.

Read on for seven reasons why you might feel dizzy when standing, plus key signs it's time to reach out to a healthcare professional.  

1. Standing up too fast

It takes additional effort for your heart to pump blood through your body when you stand up, compared to when you lie down. 

In fact, your blood pressure naturally changes based on your position in order to maintain homeostasis, a state of balance that allows your body's many systems to function properly. 

When your body gets used to functioning in a certain position, shifting positions can shock your system, so to speak, by momentarily depriving your brain of blood. 

Thanks to gravity, your blood briefly pools in your lower body when you stand up, and it may take your body a few seconds, even a minute, to adjust. Until your blood continues to circulate throughout the rest of your body, your blood pressure can fluctuate, causing dizziness.

What to do next: If you typically feel lightheaded and dizzy when standing up, these tips can help:

• Move gradually by lifting your head, your shoulders, and then easing into a sitting or standing position, Chekuri says.
• Give your body time to adjust, especially in the morning when your blood pressure is lowest. For instance, it may help to sit on the edge of your bed for a few minutes before standing up.
• Wear compression socks to increase blood flow in your legs.
• Sleep with the head of your bed elevated, or try a wedge pillow that allows you to bend at the waist.
• Drink a 15-ounce glass of water 20-30 minutes before you get out of bed, or before standing up for a prolonged period of time.
• Avoid standing for long periods of time to keep blood from pooling in your feet and causing swelling.
• Keep a journal of when you experience dizziness to pinpoint possible causes.

2. Overheating and dehydration

If you don't drink enough water, especially when it's hot out, you can easily overheat and get dehydrated. When the temperature of your environment increases, your blood pressure naturally decreases, leading to feelings of dizziness and lightheadedness.

Dehydration in itself can also affect your body's ability to regulate your temperature — when dehydrated, you sweat less, making it harder for your body to cool off. Less water in your body means less water in your blood, which can cause your blood pressure to spike or fall. 

In the short term, dehydration can thin your blood volume and lead to low blood pressure. But over time, dehydration can cause high blood pressure by triggering your brain to constrict your blood vessels.

What to do next: Staying hydrated can help regulate your blood pressure and decrease dizziness. Try these tips: 

• Drink enough water every day: Experts recommend women consume about 11.5 cups, or 92 ounces, while men should consume 15.5 cups, or 124 ounces. Just know about 20% of this water comes from the food you eat.
• Drink extra water when working out or in very warm weather.
• Try adding electrolyte solutions like Nuun, Liquid I.V., or LMNT to a cup or two of water every day to help your body stay hydrated.

3. Alcohol consumption

Alcohol can damage and narrow your blood vessels, decreasing blood flow and making your body work harder to regulate blood pressure. Consequently, you may feel a little dizzy when standing after having a few drinks. 

This dizziness, often called "the spins," happens because drinking alcohol can change the density of fluids in your ear canals and trigger vertigo.

Since a sudden change in position already affects blood pressure, adding alcohol to the mix can make it even more likely you'll feel dizzy when standing up or lying down. 

What to do next: You can try drinking coffee, eating something, or focusing your eyes on something nearby — but often, you just have to wait this feeling out. 

To avoid the spins in the future, try not to drink alcohol on an empty stomach, since that can worsen its effects on your body. Reducing the amount of alcohol you drink, or avoiding it entirely, can help prevent dizziness and more lasting side effects. 

4. Vigorous exercise

As you exercise, your muscles encourage blood flow to your heart. When you rest, your blood tends to rush back to your extremities. This rush of blood, coupled with the exertion on your lungs, means you may feel a little dizzy when standing up or moving after exercise.

Extreme or intense exercise, in particular, can drop your blood pressure and cause dizziness upon standing or changing your position, Chekuri says. Examples of vigorous exercise include: 

• Running or sprinting
• Cycling
• Weight lifting
• Swimming laps

What to do next: If you feel dizzy, nauseous, or experience blurred vision after your workout, it may help to:

• Take a few moments to sit down and lower your heart rate.
• Wait as long as you can to shower, since increasing the temperature in your environment can further decrease your blood pressure.
• Stick to exercises that don't require you to change position frequently, especially if you have low blood pressure.
• Drink plenty of water before and during exercise.

5. Medications

Certain medications may cause dizziness when standing up because they alter your blood pressure. Examples include: 

• Medications that specifically act on blood pressure, such as diuretics, beta blockers, or ACE inhibitors.
• Medications that can cause low blood pressure as a side effect, such as Prozac. 
• Medications that help treat urinary retention, such as tamsulosin (Flomax).
• Benzodiazepines such as diazepam (Valium) or alprazolam (Xanax).
• Certain antidepressants, such as tricyclic antidepressants or monoamine oxidase inhibitors (MAOIs).

What to do next: If you believe your dizziness when standing up may relate to a medication you're taking, talk to your doctor right away — but keep taking it until your doctor says you can stop. Suddenly stopping a prescribed medication may have serious health consequences.

6. Postural orthostatic tachycardia syndrome (POTS)

POTS is a more severe form of orthostatic intolerance, a condition where you may have trouble standing without feeling faint or dizzy. 

If you have POTS, your body can't regulate your blood pressure automatically, so postural changes may cause lingering dizziness. 

Other symptoms of POTS include:

• Heart palpitations
• Shortness of breath
• Headaches
• Shaking or sweating
• Trouble sleeping

What to do next: If you notice these symptoms, it's best to make an appointment with your doctor as soon as possible. They can offer more guidance on determining the underlying cause. 

In the meantime, you can take steps to minimize your symptoms by:

• Drinking enough water.
• Avoiding standing for too long at one time, especially in one position.
• Eating small, frequent meals.
• Adding more sodium to your diet.
• Trying to keep to a regular sleep schedule.
• Using a wedge pillow when you sleep, or elevating the head of your bed if possible.
• Practicing isometric exercises, which involve tightening and releasing your muscles, before sitting up or standing.

7. Current health conditions

Some health conditions unrelated to blood pressure, such as gastrointestinal (GI) problems, inner ear problems, and hormonal changes, can trigger vertigo and dizziness when standing up, Chekuri says. 

Other health issues may cause you to feel dizzy when standing up because they involve a drop in blood pressure. Examples of these conditions include:

• Heart problems
• Thyroid conditions such as hypothyroidism
• Diabetes
• Neurologic conditions, such as Lewy body dementia and Parkinson's disease
• Anemia

What to do next: The best treatment will depend on your underlying health condition. 

For instance, managing your stress levels and practicing calming techniques like meditation can help lessen nausea and dizziness caused by GI problems. 

If you think your dizziness relates to inner ear issues, on the other hand, a doctor or ear, nose, and throat (ENT) specialist can help you get a diagnosis and explain your treatment options. 

A healthcare professional can always offer more support with pinpointing causes and possible treatments for any concerning symptoms you experience. 

When to get medical attention

If dizziness when standing up makes you feel anxious about changing positions or begins to have a major impact on your health or daily routine, a good next step involves making an appointment with a healthcare professional, says Amy Sarow, a doctor of audiology at Michigan Ear Institute who specializes in hearing loss, tinnitus, and imbalance.

While brief dizziness may not pose a major cause for concern, some signs that may suggest more serious causes of orthostatic hypotension include:

• Fainting, or losing consciousness
• Falls or an inability to stand without support
• Headaches
• Dropping blood sugar, or hypoglycemia

To help determine what's causing the dizziness, your doctor may: 

• Check your blood pressure while you lie down, stand up, and sit down.
• Recommend a tilt table test to help determine the cause of the dizziness. During this test, you'll have your vitals monitored while securely strapped to a table that shifts you from a horizontal to a vertical position.
• Adjust any medications you take that can affect blood pressure, Sarow says.
• Recommend keeping a journal of when you experience dizziness to help identify possible triggers, Chekuri says.

To help prevent dizziness in the future, your doctor may recommend: 

• Staying properly hydrated.
• Eating a balanced diet that includes plenty of fruits, vegetables, and whole grains.
• Monitoring blood sugar levels.
• Getting regular physical activity by doing moderate activity — like walking, biking, or dancing — for at least 15 minutes a day. 

Insider's takeaway

Feeling dizzy when you stand up isn't always a serious health issue. But if you experience any other symptoms, such as fainting, an increase in falls, or prolonged bouts of dizziness, you'll want to schedule an appointment with a healthcare professional right away.

Your doctor can recommend tests to help determine the cause of your dizziness and rule out underlying medical conditions. They can also offer more personalized guidance on strategies to help prevent dizziness when standing up.