Insulin Pens and Needles (words 859)

Written by Hope S. Warshaw, MMSc, RD, CDE

 

The good news: the days of boiling glass syringes and sharpening needles are long gone. Today, if you must take insulin by injection, you have an increasing array of options. Choose from pre-filled or reusable insulin pens or a variety of sizes of syringes and width and lengths of syringe and pen needles. Perhaps one of these new options will help you make taking insulin more convenient, easier, and less painful.  

 

Is an Insulin Pen for You?

Insulin pens have been around nearly a decade. More people use pens today because there are more options. Plus, with the new longer and shorter acting insulins, people take more shots. The pens make carrying insulin with you more convenient and make frequent injections easier to take. Note: at present Lantus (glargine) isn’t available in a pen.

 

Most insulin pens are the size of a large fountain pen. The insulin is contained within the pen. You attach a needle, prime the needle, dial up a dose, inject, push a trigger, and hold. Done! Insulin doses can be very accurate. Some pens come pre-filled and some use a replaceable pre-filled cartridge. They most often hold about 300 units of insulin and deliver insulin in 1 unit increments. For young children or adults on low insulin doses there are mini or junior pens. They deliver in ½ unit increments.

 

Before you choose a pen, make sure the pre-filled pen cartridge or pre-filled pen is available in the types of insulin you use. Also, make sure that your health plan covers the type of pen you want to use.

 

Because you will keep your pen at room temperature and portable, be aware of the number of days the insulin you use can be at room temperature. Find this information on the package insert. Mark on the pen the date you start using it and when you should discard it. Note: you should do this on any insulin pen or vial you use.

 

Instead of buying syringes and vials, you buy pen needles and disposable pens or insulin cartridges. Read about pen needles below. The three companies that make the most common pens are: Becton Dickinson, Eli Lilly and Novo-Nordisk. Find their contact information below.

 

Several other insulin delivery devices or dual insulin delivery and blood glucose monitoring devices are available. The Innolet (pre-filled) and Innovo (uses cartridges) are easy to use insulin delivery devices with large display features. The InDuo is a combo insulin pen and blood glucose meter. The meter is Lifescan’s Ultra. More information on these products is available from NovoNordisk.

 

Discuss switching to a pen or other insulin delivery device with your health care provider or diabetes educator. If the pen is for you, learn your options, proper use of the pen and pen needles, and proper insulin storage.

 

Syringe and Pen Needles: Length and Thickness

When you buy insulin syringes, you have three decisions—needle length and thickness or gauge and cartridge size. When you buy pen needles, you have two decisions—the needle length and thickness or gauge. The trend in needles is shorter and thinner. That’s great because they can cause less pain.

 

Needle length:                                                                          

Two needle lengths are available for syringes—5/16", so-called short, ½", so-called long. Three needle lengths are now available for pen needles—3/16”, so-called mini, 5/16", so-called short, ½", so-called long. Adults should start with the ½” short. Children who use pens should start with the 3/16” mini. If blood glucose cannot be controlled and excess weight is an issue, use a longer needle to improve insulin absorption. 

 

Needle Gauge or Thickness:

The gauge is the diameter of the needle, or width—the higher the number, the thinner the gauge. Syringe needles are available in three gauges—28, 29, and 30. Pen needles are available in 29, 30, and 31 gauge. Different companies make syringe and pen needles in different gauges. The thinnest insulin syringe is 30 gauge, the thinnest pen needle is 31 gauge. 

 

Syringes and pen needles don’t come in every length and width. Common syringes sizes are 30 gauge with a 5/16” needle, and 28 and 29 gauge with a ½” needle. Common pen needle sizes are 31 gauge with a 3/16” and 5/16” needle and 29 gauge with a 1/2” needle.

 

Another Decision: Syringe size

There are three sizes—3/10cc (holds 30 units), ½cc (holds 50 units), and 1cc (holds 100 units).

If you regularly take:

• a few units less than 30 units total at one time, use a 3/10 cc syringe
• between 30 and 50 units total at one time, use a 1/2 cc syringe
• more than 50 and 100 units total at one time, use a 1 cc syringe

Note: on the 3/10 and ½ cc syringes, each line equals one unit of insulin.  On the 1cc syringe, each line equals two units.

 

Manufacturer’s websites:

Becton Dickinson and Company – www.bddiabetes.com or 888-BDCARES 888-232-2737

Eli Lilly and Company – www.lillydiabetes.com or 800-545-5979

Novo-Nordisk Pharmaceuticals – www.novonordisk-us.com or 800-727-6500

 

For more details review the Resource Guide in the January 2003 issue of Diabetes Forecast, American Diabetes Association. This is posted on their web site at: www.diabetes.org/main/community/forecast/jan_2003_toc.jsp

 

Written by Hope S. Warshaw, MMSc, RD, CDE