What Are Pen Needles?

Article Details
  • Written By: Mary McMahon
  • Edited By: Shereen Skola
  • Last Modified Date: 06 August 2019
  • Copyright Protected:
    Conjecture Corporation
  • Print this Article

Pen needles are disposable components for injection pens used to dispense medication. These medical supplies are commonly used by patients who need regular injections, like people with diabetes who take insulin. The pen can be used over and over again, while the needle can be changed for each use for smooth performance. Several brands of pens and accessory needles are produced and it is important to select the right one for a patient’s needs. Patients can receive advice and instructions on which pen to buy from their care providers.

These devices include a small needle on a mounting cap which can be twisted or clipped into the pen. A shield covers the needle until it is ready for use to keep it sterile and prevent needlestick injuries. Patients can insert a cartridge of medication into the pen, rather than having to draw an injection out of a vial. When they want to take their medication, they uncap the pen and perform the injection. Some pens have a retractable design to withdraw the needle after use, which prevents injuries.


Like other needles, pen needles are classified by gauge and length. Some medications require a wider gauge because they are thick or chunky, and cannot move smoothly through a small needle. The smaller the needle, the more comfortable the injection, so patients have to balance these two needs when they select a product. Length is also an important consideration. Injection sites may require a longer needle for full penetration if they are deeper beneath the skin.

Patients are usually advised to use pen needles only once, for several reasons. The first is comfort. With each use, a needle dulls, and over time can become more uncomfortable to use. Additionally, multiple uses can increase the risk of infection, which is not desirable. Disposing of needles immediately after use can also protect other people by limiting the chances of a needlestick injury and removing potentially infectious materials to keep an environment clean and safe.

Packages of pen needles may contain loose needles or could come with a dispenser. In all cases, the caps keep the needles covered until they are ready to use. Dispensers may have a built in disposal chamber. This allows patients to remove old needles and discard them in a safe container. When the pen needles are used up, the disposal chamber will be full, and it can be picked up by a medical waste company or dropped off for disposal.



Discuss this Article

Post your comments

Post Anonymously


forgot password?