Which syringe and needle do I use, and what if something goes wrong when I draw or inject?

This article covers technique questions that apply to more than one Belle medication: syringe sizes, needle length, drawing a dose from one or two vials, and what to do when a needle bends or breaks. For the step-by-step GLP-1 injection (semaglutide or tirzepatide), see "How do I store, handle, and inject my GLP-1 medication?". For muscle injections such as MIC-B12, see "How to Give an Intramuscular (IM) Injection".

The short version: use a new syringe for every injection, never put a syringe that has touched your body back into a vial, and if any medication may have gone in, do not repeat the dose. Take your next dose on your usual day and message us.

About the syringes in your shipment

Your syringes are prescribed items. They are dispensed by the pharmacy that fills your order and are listed on your prescription paperwork.

If what you received does not look like what your paperwork lists, or you would like the manufacturer, model, or product documentation for your syringes, the pharmacy is the one that holds that information. Contact the pharmacy using the number provided with your order. You can also send us a message and we will help you get in touch.

Can I use a 0.5 mL syringe instead of the 1 mL syringe?

Yes, if your dose is 50 units or less. The unit markings are the same on both syringes. The only difference is how much the syringe can hold. Draw to the same unit mark you would have used on the 1 mL syringe.

If your dose is more than 50 units, a 0.5 mL syringe will not hold it. Use the 1 mL syringe. If you are not sure how many units your dose is, check your prescription label or contact us before drawing.

Which needle do I use?

The needle depends on how the medication is given:

• Glutathione is injected subcutaneously (under the skin). Use the short needle.
• MIC-B12 is injected intramuscularly (into the muscle). Use the long needle.
• GLP-1 medications (semaglutide and tirzepatide) and NAD+ are injected subcutaneously. Follow the instructions in their own articles.

Do not use the same technique for subcutaneous and muscle injections. If you are not sure which needle goes with which medication, check your prescription label or ask us before injecting.

Drawing your dose: common questions

Is it okay to push medication back into the vial?

Yes. If you are pushing the same vial's own medication back into that vial, it does not affect the medication or the vial. This is also how many people work out air bubbles: you can push the medication back in and draw it again, including to draw a slightly higher amount. A new needle and syringe are still needed for each injection.

Does pushing medication back into the vial affect sterility?

No, as long as the medication has been stored correctly and the syringe is clean.

The one rule that matters: you can only push back into the vial and redraw if the syringe has only touched the vial. Never put a syringe back into a vial after it has touched your body. That syringe is used and cannot go back in.

What if there is not enough medication in one vial for my full dose?

If both vials have the same concentration (the same mg/mL printed on the label), you can split your dose between two syringes, drawing part of the dose from each vial. Because the concentration is the same, the unit markings mean the same thing for both. Each syringe is used for one injection only. If the two vials have different concentrations, do not combine them. Contact us first.

If a needle bends or breaks

A needle keeps bending when I inject.

Do not use a bent needle. The needle on your syringes is built in and cannot be changed, so use a new syringe instead. To lower the chance of it bending, insert the needle straight in (90 degrees) in one quick motion, as shown in your injection steps. If you keep bending needles even with a straight, quick insertion, message us so we can look at your technique with you.

My needle bent or broke going into the vial, while I was drawing my dose.

Put that syringe in your sharps container and use a new syringe. To make the needle go into the vial more easily, take the vial out of the fridge about 10 to 15 minutes before you draw, so the rubber top softens, then push the needle into the vial slowly and steadily.

My needle broke or bent with medicine in the syringe, before I injected.

Draw a fresh dose with a new syringe. The needle on your syringes is built in and cannot be swapped, so put the old syringe, with the medicine still in it, in your sharps container. Do not try to move the medicine from a damaged syringe into another syringe or back into the vial. It is no longer sterile once it leaves the syringe that way, so it cannot be saved.

Part of the needle broke off inside the vial.

Message us with a photo of your vial, and do not use it or try to get the piece out until our care team has reviewed.

Some medicine may have gone in, it leaked, or you are not sure.

Do not inject more to make up for it. This applies if you pushed the plunger even part of the way, medicine leaked out or made a bubble under your skin, the needle broke or came out partway through, or you are not sure how much went in. A top-up on a dose that partly went in can give you more than your prescribed amount, which raises the chance of strong side effects such as vomiting. Take your next dose on your usual day, as prescribed, and message us so your care team knows what happened.

If any part of a needle stays in your skin, get medical care right away. For severe or life-threatening symptoms, call 911 or go to the ER.

After you inject

Do not rub the injection site. Rubbing does not help absorption and can make irritation worse. If the spot is irritated afterward, see the injection site section of your medication's article.

Does my injection site change how well the medication works?

Everyone responds a little differently. Some patients notice a difference in how they feel, or in side effects, when they switch spots, and others do not. If you want to try a different area, that is fine: you can rotate between the approved areas for your medication and go back to your usual spot if the change does not help. For which areas are approved, see the article for your medication. For GLP-1 medications, the approved areas are the abdomen, front of the thigh, and outer upper arm.

This guide is patient education, not a prescription. Your own prescription label and the instructions from your care team take precedence over anything on this page. If the two conflict, follow your label and reach out through the Belle patient portal.