Pen needles are used in conjunction with injection pens to deliver injectable medications into the body. Pen needles are used in conjunction with injection pens to deliver injectable medications into the body. A pen needle consists of a hollow needle which is embedded in a plastic hub and attaches to injection pens. Pen needles come in a variety of needle lengths and diameters and are used by health professionals and patients for injection of a variety of medications. They are commonly used by people with diabetes who often require multiple daily insulin injections. Needle technology has changed over the past decades. Many years ago home use syringe needles were large, and had to be sterilized and sharpened by hand by patients themselves. Today’s pen needles are engineered and manufactured for greater comfort and ease of use with electro-polishing for needle smoothness; thin, fine point tips for ease in penetration; lubrication for less friction and more glide; plastic caps for safety; and individual wrapping for sterility. Injection pen and pen needles are an alternative drug delivery method to the traditional vial/syringe method.