This Is MS Multiple Sclerosis Community: Knowledge & Support

In using the dry powdered form of Avonex, I've developed the following injection technique which is a modification of the instructions in the doctor's prescribing information which is packaged with the medication. I've discovered that if you remove all of the air from the syringe prior to the IM injection, then there will be about 65 µL which will remain in the syringe. With Avonex, this represents a loss of about 2 µg of the medication. As an alternative, I dilute the vial with 1.2 mL, and after attaching the needle, add about 4 air bubbles (roughly 200 µL of air) to the syringe after inverting it, and inject the whole lot. This method leaves only about 5 µL in the syringe and maximizes my dosage to about 32.5 µg (in this approximation I've taken into account that there are probably a few µL of fluid stuck to the side of the vial which cannot be removed). The nurse representative from Biogen did not feel that injecting a small amount of air intramuscularly would be a problem.

NHE

Although she's using the pre-filled form of Avnoex, my girlfriend was told by biogen's nurse she'd better injecting a small amount of air than loosing some Avonex in the syringe or out of the syringe by trying tu put out the bubble. So you're probably right.

Here's another tip for anyone using the powdered form of Avonex. When you're ready to add the sterile water to the vial containing the dried Avonex, hold the vial and syringe horizontally so that the water will gently run down the side of the vial as it contacts the dried Avonex pellet. This will prevent it from dripping directly onto the pellet which can cause bubbles to form.

NHE

I'm pretty sure I hit a blood vessel last week when I did my injection... the injection hurt more than usual, the medicine burned going in, and then when i pulled the needle out, there was alot of blood.... the next day, i had a bruise in the shape of a line.

the strange thing is, i *did* pull back the plunger after the poke, and there was no blood!

In a recent conversation with Avonex (and during my injection training), they said pulling back the plunger is NOT required... Is anyone else concerned about pushing air into a blood vessel? can't that be very very very bad?

You may have nicked a blood vessel with the needle on the way in, but that blood vessel was not near the end of the needle when it was at its final depth. That would explain why there was no blood when you did the pull back. I've only had blood in the syringe from the pull back on one occasion. I just pulled the syringe out and stuck it back in about a half inch to an inch away from the original site and all was well. Every once in a while I get an injection site that bleeds once the needle is removed. One time the blood was dribbling out fast enough that I just put my finger on it to stop the bleed. However, I rarely need the little gauze pad that comes with the weekly injection kit.

I know that Biogen has changed their recommendations about the pull back, but that's how I was trained to do it so I continue doing it. It does help to insure that the medication is being injected into the muscle instead of directly into the blood stream. I think that Biogen changed its recommendation since they probably found no difference in long term effectiveness either way. However, injecting into the muscle causes the medication to be absorbed more slowly so the side effects may be less intense. Just a theory there, I don't know for certain.

I've gotten a small quarter sized bruise on occasion. Over the 9 years I've been on Avonex, this has probably happened roughly less than a half dozen times. I find that the injection goes better for me if I inject in the upper third of my thigh muscle over towards the outside edge (sort of where your middle or ring finger would be if you stuck your hand in your front pants pocket). Most of the time, the injection site doesn't even bleed much and I've found that I need to keep a finger near where I pulled the needle out so I know where to put the band-aid.

Air into the muscle is not a problem. As I've mentioned in the prior post, you want to have about 0.2 mL of air at the top of the syringe near the plunger to insure that all of the medication is pushed out of the syringe.

NHE