Feeling dizzy or lightheaded when you stand up is a common experience — but when it happens frequently or severely, it may be a sign of an underlying condition like Postural Orthostatic Tachycardia Syndrome (POTS).
What Causes Dizziness When Standing?
When you stand up, gravity pulls blood toward your legs. Your body normally adjusts by:
- Constricting blood vessels in your legs
- Slightly increasing your heart rate
- Maintaining blood pressure to your brain
If this adjustment doesn't happen properly, less blood reaches your brain temporarily, causing that dizzy, lightheaded feeling. This is called orthostatic intolerance.
Is It Normal?
Occasional, brief dizziness when standing quickly is common and usually harmless, especially if you:
- Haven't eaten or had enough fluids
- Stood up too quickly after lying down for a long time
- Are in a hot environment
- Are taking certain medications
When to Be Concerned
Dizziness when standing may indicate a problem if:
- It happens frequently (daily or multiple times a week)
- It's severe enough to affect your daily activities
- It doesn't improve after drinking water or eating
- It's accompanied by a racing heartbeat
- You've almost fainted or actually fainted
- It started after a viral illness (like COVID-19)
Could It Be POTS?
POTS (Postural Orthostatic Tachycardia Syndrome) is a condition where your heart rate increases excessively when you stand up. This can cause:
- Dizziness or lightheadedness
- Feeling like you might faint
- Racing or pounding heart
- Brain fog
- Fatigue
- Symptoms that improve when lying down
The key difference with POTS is that your heart rate increases significantly (30+ bpm in adults) when you stand, and symptoms persist rather than resolving within a few seconds.
Other Conditions That Cause Orthostatic Dizziness
Dizziness when standing isn't always POTS. Other possible causes include:
- Orthostatic Hypotension: A drop in blood pressure when standing (different from POTS)
- Dehydration: Not enough fluid in your body
- Anemia: Low red blood cell count
- Medication side effects: Blood pressure medications, antidepressants, and others
- Inner ear problems: Conditions affecting balance
- Heart conditions: Various cardiac issues
- Neurological conditions: Affecting the nervous system
This is why it's important to see a healthcare provider for proper evaluation.
Gathering Data for Your Doctor
If you're experiencing frequent dizziness when standing, tracking your symptoms and gathering objective data can help your healthcare provider understand what's happening.
What to Track
- When the dizziness occurs (time of day, triggers)
- How severe it is (mild, moderate, severe)
- How long it lasts
- What makes it better or worse
- Other symptoms that occur at the same time
Measuring Your Heart Rate Response
POTS Check can help you measure exactly how your heart rate responds when you stand up. This gives you objective data to share with your doctor, rather than just describing subjective symptoms.
How POTS Check Helps
- Measures your resting (baseline) heart rate
- Tracks heart rate as you stand up
- Calculates the change in heart rate (ΔHR)
- Records any symptoms during the test
- Generates a PDF report for your doctor
What to Do If You're Frequently Dizzy
- Stay hydrated: Drink plenty of water throughout the day
- Stand up slowly: Give your body time to adjust
- Track your symptoms: Note patterns and triggers
- Screen at home: Use POTS Check to measure your heart rate response
- See a healthcare provider: Share your data and discuss your symptoms
When to Seek Immediate Care
Seek emergency medical attention if dizziness is accompanied by: chest pain, shortness of breath, severe headache, confusion, numbness or weakness, vision changes, or if you actually faint.