Lyme, POTS & Dysautonomia: Why Your Heart Races When You Stand Up

Of all the strange, scary symptoms Lyme threw at me and the people I support, the one that most often gets waved away as "anxiety" is this: a heart that races the moment you stand, dizziness that drops you back into a chair, and a bone-deep exhaustion that gets worse the more upright you are. It's frightening. It's real. And it isn't in your head.

The umbrella term is dysautonomia — dysfunction of the autonomic nervous system, the automatic control panel that runs your heart rate, blood pressure, digestion, and temperature without you thinking about it. The most talked-about form is POTS (Postural Orthostatic Tachycardia Syndrome). And there's a well-recognized overlap between chronic Lyme, its co-infections, and this exact cluster of problems. Dysautonomia also travels closely with MCAS (mast cell activation) — if you also react to foods, smells, and heat, the two are worth looking at together.

What are dysautonomia and POTS?

Your autonomic nervous system handles everything you never have to think about — heartbeat, blood pressure, blood-vessel tone, digestion, sweating, temperature. When it misfires, that's dysautonomia.

POTS is a specific, common form of it. The clinical definition: when you stand, your heart rate jumps by at least 30 beats per minute (40 in teens) within ten minutes — without a big drop in blood pressure — along with symptoms that ease when you lie down. In plain terms: your body can't properly regulate blood flow against gravity, so your heart compensates by racing.

Why Lyme & Bartonella cause it

Here's the connection. The autonomic nervous system runs on delicate nerves — including tiny "small fiber" nerves — and it's sensitive to inflammation. Chronic Lyme and co-infections, especially Bartonella, can disrupt it several ways:

• Autonomic & small-fiber nerve damage — the infection and immune response can injure the very nerves that regulate blood flow.
• Chronic inflammation — persistent neuroinflammation interferes with autonomic signaling.
• Autoimmune activity — some people develop autoantibodies that target autonomic receptors.
• Low blood volume & blood pooling — common in POTS, leaving less blood to circulate when you stand.

Bartonella in particular shows up again and again in the dysautonomia conversation, which is one more reason getting the full co-infection picture matters so much. And there's a hopeful thread here: because the dysfunction is often driven by the underlying infection and inflammation, treating the root can sometimes improve autonomic symptoms too.

The symptoms (it's more than a racing heart)

POTS and dysautonomia are sneaky because they touch so many systems. People are often stunned to learn this whole list can trace back to one autonomic problem:

• Racing heart / palpitations on standing
• Lightheadedness & dizziness
• Fainting or near-fainting
• Bone-deep fatigue
• Brain fog & poor concentration
• Exercise intolerance
• Shakiness & adrenaline surges
• Temperature dysregulation
• Nausea & digestive issues
• Blood pooling (purple, cold feet)
• "Coat-hanger" neck & shoulder pain
• Symptoms worse in heat or after meals

Sound familiar? A lot of what gets lumped into "Lyme fatigue" or brain fog may actually have an autonomic driver worth investigating.

How it's diagnosed

The good news is that unlike a lot of Lyme symptoms, POTS is measurable. Doctors use:

• Tilt-table test — you're secured to a table that tilts upright while your heart rate and blood pressure are monitored.
• Active stand test / NASA lean test — a simpler in-office (or even at-home, with guidance) version measuring your heart rate lying down and standing.

That objective heart-rate jump is powerful, because it turns "I feel awful when I stand" into a number on a chart — exactly the kind of proof that gets you taken seriously (and, if relevant, helps document disability claims).

What actually helps

"It's just anxiety" — no, it isn't

I need to say this plainly because so many of us were told it for years: a racing heart, adrenaline surges, and shakiness are physical autonomic events. They can absolutely feel like panic — and being repeatedly disbelieved will genuinely make anyone anxious — but the root here is a dysregulated nervous system, not a character flaw or a mental weakness. You are allowed to ask for a tilt-table test. You are allowed to want a number on a chart.

Here's the honest bottom line I'd give a friend: if standing up makes your heart pound and your head swim, that deserves a real workup — not a shrug. Dysautonomia and POTS are recognized, measurable, and manageable, and for many people with Lyme, naming it is the first time the whole confusing picture finally makes sense.

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Medical disclaimer: This article is for educational purposes only and reflects personal experience and general information. It is not medical advice, diagnosis, or treatment, and it does not replace consultation with a qualified healthcare professional. POTS and dysautonomia require proper medical evaluation and management, and treatments (including salt/fluid loading and medications) are not appropriate for everyone. Christina Carter is a patient advocate and educator, not a licensed medical provider. Always consult a qualified clinician before starting, stopping, or changing any treatment.