Acupuncture needles are usually inserted for 10-15 minutes into the subcutaneous tissues, but can be left for as long as 30 minutes, depending on the condition being treated. Needles that are left in for too long can overstimulate the points, making the patient feel very tired. ASP Semi-Permanent Ear Acupuncture Needles, however, typically stay in for at least two days after the treatment session.