VasoVagal Response
Ever felt lightheaded during a medical procedure? Maybe even passed out? That might’ve been a vasovagal response — a fancy medical term for something that’s more common (and scarier sounding) than it really is.
So… What Is a Vasovagal Response?
Let’s strip it down:
A vasovagal response is your body’s way of protecting itself — typically triggered by stress, pain, or anxiety. It slows your heart rate, drops your blood pressure, and causes reduced blood flow to the brain. Result? You faint.
It’s your parasympathetic nervous system saying, “Whoa, things are too intense. Let’s chill... a little too hard.”
Why Talk About This in a PT Setting?
Because it can happen during dry needling. While rare (less than 1% of cases), it’s something physical therapists need to be ready for. I’ve been dry needling for over four years and have had three patients faint during or right after treatment.
It’s not common — but it’s real.
How It Happens: A Quick Breakdown
The needle triggers a pain signal (aka a noxious stimulus).
Your sympathetic system (fight or flight) spikes.
Your parasympathetic system counters it — but sometimes overcorrects.
Heart rate slows → Blood pressure drops → Brain doesn’t get enough oxygen.
Brain says: "Nope." → You faint.
Common Triggers in Patients
Fear of needles
High pain levels
Dehydration
Low blood sugar
High stress or anxiety
Being in an upright seated position during needling
I’ve noticed it never happens when a patient is lying flat, but when they’re upright — gravity makes that blood pressure drop even more impactful.
What It Looks Like
You might see:
Patient goes quiet
Slumped posture or head in hands
Complaints of feeling “off,” dizzy, or nauseous
Pale skin or sweating
Loss of consciousness for 5–10 seconds
From the PT side, staying calm is key. Unhook electrodes, remove needles, support the patient, and get help if needed. Always have a clear emergency plan.
For Therapists: Be Prepared
Know the signs
Keep tools, sharps containers, and phones within reach
Avoid leaving patients alone during treatment
Be trained in basic emergency response
Have a plan, especially if doing concierge or mobile care
For Patients: Be Honest and Hydrated
Before dry needling, tell your therapist if you’ve ever:
Fainted while donating blood
Felt queasy during medical procedures
Had a vasovagal response in the past
Also, eat beforehand, stay hydrated (coffee doesn’t count!), and try to arrive as relaxed as possible.
Final Thoughts
Dry needling is an incredibly useful tool in physical therapy — but even with rare risks like vasovagal responses, preparation and communication are key. Whether you’re a clinician or patient, the more you know, the safer and smoother the experience will be.
Want the longer version of this conversation? Listen to the full episode on Spotify or Youtube🎙️
