Orthostatic Hypotension from Medications: Why You Feel Dizzy When You Stand Up

Standing up and feeling like the room is spinning? That sudden wave of dizziness, blurred vision, or even blacking out isn’t just bad luck-it could be your medications. This isn’t normal aging. It’s orthostatic hypotension, a sharp drop in blood pressure when you rise from sitting or lying down. And for many people, especially those on multiple prescriptions, it’s not a side effect-it’s a warning sign.

What Exactly Is Orthostatic Hypotension?

Orthostatic hypotension means your blood pressure plummets within three minutes of standing. The medical definition is clear: a drop of 20 mm Hg in systolic pressure (the top number) or 10 mm Hg in diastolic (the bottom number). That’s not a small fluctuation. It’s enough to starve your brain of oxygen, causing dizziness, lightheadedness, or fainting. It’s not rare. About 5% to 30% of older adults experience it, and up to 30% of those cases are directly caused by medications.

Here’s the thing: your body normally adjusts when you stand. Blood vessels tighten, your heart beats a little faster, and your blood pressure stays steady. But certain drugs interfere with that system. They block the signals your nerves send to your blood vessels. They make you lose fluid. They calm your nervous system too much. The result? Your blood pressure crashes when you stand-and your body doesn’t fix it fast enough.

Which Medications Are Most Likely to Cause This?

Not all drugs cause this. But some are notorious. If you’re taking any of these, pay attention to how you feel when you stand up.

• Antipsychotics like quetiapine, clozapine, and chlorpromazine: These can cause dizziness in 20% to 40% of users, especially at higher doses. One patient on Reddit said, "After starting quetiapine, I fainted twice in three weeks. My blood pressure dropped from 128/82 to 92/61 in two minutes."
• Alpha-blockers like doxazosin and terazosin: Used for high blood pressure or enlarged prostate, these relax blood vessels so much that standing can trigger a sudden drop. The risk is 2.8 times higher than with other blood pressure meds.
• Tricyclic antidepressants like amitriptyline: These affect nerve signals and fluid balance. Studies show they nearly triple the risk of orthostatic hypotension.
• Diuretics like hydrochlorothiazide: These make you pee out extra fluid. Less fluid in your blood vessels means less pressure to push blood to your brain when you stand. One 78-year-old patient had repeated falls. After stopping hydrochlorothiazide, the dizziness vanished in 72 hours.
• Opioids like oxycodone and morphine: These slow down your nervous system. About 15% to 25% of older adults on opioids report dizziness on standing-and that risk jumps 2.3 times if they’re also taking benzodiazepines or drinking alcohol.
• Levodopa (for Parkinson’s): Up to half of patients on this drug develop orthostatic hypotension. It’s not the Parkinson’s itself-it’s the medication.

It’s not just the drug-it’s the combo. People on four or more medications have over five times the risk. That’s why polypharmacy is such a silent danger.

Why This Isn’t Just "Getting Older"

Many people think dizziness on standing is just part of aging. It’s not. Yes, your body’s ability to regulate blood pressure declines after 70. But that doesn’t mean you have to live with it. The real problem is that doctors often miss the link between meds and symptoms. A Mayo Clinic study found that 55% of patients had dizziness for over two months before anyone connected it to their pills.

And it’s not harmless. Orthostatic hypotension increases your risk of falling by 15% to 30%. Falls lead to broken hips, brain injuries, hospital stays, and even death. Studies show people with this condition have a 24% to 32% higher risk of dying over 10 years-not because of the drop in blood pressure itself, but because of the injuries it causes.

How Is It Diagnosed?

Your doctor doesn’t guess. They measure. The standard test is simple:

1. Rest lying down for five minutes.
2. Take your blood pressure.
3. Stand up.
4. Measure again at 1, 2, and 3 minutes.

If your systolic pressure drops 20 points or more, or your diastolic drops 10 points or more, and you feel dizzy at the same time-you have orthostatic hypotension. Some people have the drop without symptoms. That’s why it’s called "silent." But if you feel lightheaded when you stand, even once, it’s worth checking.

What Can You Do About It?

The good news? Medication-induced orthostatic hypotension is often reversible. Up to 70% to 85% of cases improve once the drug is adjusted. Here’s what works:

• Review your meds with your doctor. Don’t stop anything on your own. But ask: "Could any of these be causing my dizziness?" Be ready to list every pill, patch, or supplement you take.
• Change the timing. Take blood pressure or diuretic meds at night instead of morning. That way, the peak effect happens while you’re lying down.
• Slow down. When you get up, sit on the edge of the bed for 30 seconds first. Then stand slowly. Don’t rush. Use a cane or hold onto furniture if needed.
• Hydrate. Drink 2 to 2.5 liters of water daily. Fluids help keep your blood volume up. Avoid large meals-they can pull blood away from your brain.
• Wear compression stockings. These help push blood back up from your legs. They’re not glamorous, but they work.
• Don’t stand still. If you’re standing in line, shift your weight, wiggle your toes, or march in place. Movement keeps blood flowing.

If those steps don’t help, your doctor might consider midodrine-a medication that tightens blood vessels. It’s not first-line, but for people who still fall despite lifestyle changes, it can reduce symptoms by 65%.

What’s the Bigger Picture?

This isn’t just about one person feeling dizzy. It’s a public health issue. Falls from orthostatic hypotension cost Medicare $31 billion a year. And 30% to 40% of those costs come from drug-induced cases. Since 2020, the FDA has required drug labels to warn about orthostatic hypotension if it happens in more than 5% of trial patients. The American Geriatrics Society now lists 12 high-risk drugs for seniors.

Doctors are getting better at screening. In 2023, 82% of geriatric practices now check for orthostatic hypotension during routine visits. But it’s still underdiagnosed. If you’re over 65, on multiple meds, and feel dizzy when standing-speak up. Your doctor might not think to ask.

What’s Next?

Research is moving fast. Scientists are testing drugs that target specific receptors to lower blood pressure without triggering dizziness. There are also genetic tests in development to predict who’s more likely to have this reaction. In the meantime, the best tool you have is awareness.

Medication-induced orthostatic hypotension is preventable. It’s treatable. And it doesn’t have to be part of your daily life. You don’t need to live with dizziness. You just need to know what to look for-and who to talk to.

What to Do Next

If you or someone you care about is feeling dizzy when standing:

• Write down every medication, including doses and times you take them.
• Track when the dizziness happens-right after standing? After meals? After taking a pill?
• Ask your doctor: "Could any of these meds be causing orthostatic hypotension?"
• Request a blood pressure check while lying down and standing.
• Don’t accept dizziness as normal. It’s a signal. Listen to it.

Your health isn’t about taking more pills. It’s about taking the right ones-safely. And if standing up leaves you dizzy, you deserve better than just living with it.