Idiopathic OH: Causes, Symptoms, and What You Can Do

When you stand up and suddenly feel dizzy, lightheaded, or like the room is spinning, it might be idiopathic OH, a form of orthostatic hypotension with no identifiable underlying cause. Also known as primary autonomic failure, it happens when your body doesn’t adjust blood pressure fast enough after standing, leaving your brain temporarily starved of blood. Unlike secondary orthostatic hypotension—which comes from diabetes, Parkinson’s, or medications—idiopathic OH stands alone. No tumor. No nerve damage from disease. Just your autonomic nervous system failing to do its job, for reasons doctors still don’t fully understand.

This isn’t just about feeling a little woozy. People with idiopathic OH often collapse without warning, struggle to stand in line, or can’t walk more than a few steps without needing to sit down. It affects daily life hard: showering, grocery shopping, even getting out of bed can become risky. The condition mostly hits adults over 50, but it’s not rare in younger people with autonomic dysfunction. It’s not caused by dehydration or being out of shape. It’s a neurological glitch. And it’s more common than most people think.

What makes idiopathic OH tricky is that it looks like other problems. Is it anxiety? Low iron? Too much caffeine? But if you’ve ruled out those and still get dizzy every time you stand, it’s worth asking about orthostatic hypotension, a drop in blood pressure upon standing. And if no cause is found after testing, you’re looking at idiopathic OH. Treatment isn’t one-size-fits-all. Some people need more salt and water. Others need compression stockings or medications that tighten blood vessels. A few find relief with simple tricks—crossing your legs, tensing muscles before standing, or sleeping with the head of the bed slightly raised.

There’s no cure yet. But understanding how your body reacts—and learning how to outsmart it—can turn a disabling condition into something manageable. Below, you’ll find real-world guides on medications that help, lifestyle changes that work, and how to spot when it’s something worse. These aren’t theoretical tips. They’re from people who’ve lived with this, and doctors who’ve treated it.