This is the most common question asked about acupuncture because many people associate needles with pain. Acupuncture needles are about the thickness of a dog’s whisker, so they are virtually painless when inserted. After insertion, the practitioner will bring the needle to the appropriate depth. You will then usually feel a very unique sensation that can vary from tingling, to heaviness, to warmth, or nothing at all. Each person’s experience is different.