Filling the reusable insulin injection pen cartridge is a precise process that requires maintaining a sterile environment.  An instructional video is included on this page.  Please read the directions first before filling your pen.

Preparation

• Sanitize: Wash your hands thoroughly and clean the rubber stoppers of your medication vial and the glass cartridge with a fresh alcohol swab.

• Equipment: You will need a sterile syringe (typically a 3mL syringe with a 1-inch needle is used for filling cartridges) and your Bacteriostatic Water or medication.

The Filling Process

Draw Air: Pull the plunger of your syringe back to the amount of liquid you intend to draw (e.g., if you are filling a 3mL cartridge, draw 3mL of air).

Equalize Pressure: Insert the needle into your medication vial and inject the air. This makes it easier to withdraw the liquid.

Withdraw Liquid: Invert the vial and pull back the plunger slowly to fill the syringe. Tap the side of the syringe to move any air bubbles to the top and push them back into the vial.

Fill the Cartridge: Insert the needle into the rubber end of the empty glass cartridge. Slowly inject the liquid. If the cartridge has a movable plunger (piston), you will see it slide back as the liquid enters.

Check for Bubbles: Once filled, inspect the cartridge. If there are large bubbles, you can gently tap the glass and use the syringe to draw them out before removing the needle.

Loading the Pen

Insert Cartridge: Unscrew the pen body, place the filled cartridge into the holder (narrow end toward the needle tip), and screw the pen back together.

Prime the Pen: Attach a new pen needle. Dial a small dose (usually 2 units) and hold the pen upright, pressing the button until a drop of liquid appears at the tip. This ensures all air is out of the system before use.

Storage: Keep the loaded pen in the refrigerator unless the specific instructions for your medication state otherwise.

Important Safety Note: If you are reconstituting lyophilized (powder) medications for use in these cartridges, always aim the stream of liquid down the side of the glass wall rather than directly at the powder to avoid damaging the delicate compounds.