Acupuncture is generally painless. It even has a calming effect and increases a sense of well-being, partly by releasing endorphins. However, a patient who is normally not sensitive to needle insertion may occasionally feel a slight prick. While the experience doesn’t reduce the overall treatment comfort, it does often cause wonderment as to why it occurs.
This doesn’t apply to pain due to poor needling technique from either inexperience or distraction; or to apprehension that may result in hypersensitivity. Rather, these are my thoughts on what is happening during the random instances of needle sensitivity.
The skin is our first line of defense against external threats. Its dermal layer is made of dense irregular connective tissue, mimicking a woven fabric that absorbs forces from a multitude of directions. This ensures our skin doesn’t tear from the slightest impact.
Acupuncture needles are finely honed, with a diameter that is often less than or equal to that of head hair. So its profile isn’t a threat, and the connective tissue normally separates to accommodate needle insertion.
Sometimes the angle of insertion may allow the needle to catch on the tissue fabric, triggering a nerve signal and pricking sensation. Not a big deal. We can normally disregard the sensation because it’s so fleeting, or adjust the needle angle to prevent irritation.
Dehydration can also play a role by causing irritability of the sensory nerves; or increasing the friction between tissue fibers, elevating puncture resistance. While we can’t stop a bullet with our skin, we can hinder artful needling technique. So, as always, stay hydrated.