Weight Loss Pen vs. Syringe: Which Is Best for You?

Glucagon-like peptide-1 receptor agonists (GLP-1s) are a class of type 2 diabetes and weight loss medication that can be delivered through an injection — think brand names like Ozempic^®, Zepbound^®, and Saxenda^®.

These medications are available in pre-filled injection pens or syringes, which you use to draw the medication out of a vial.

The setup differs slightly for a pen versus syringe, and different meds are available in different forms. But both delivery methods are effective (when done correctly, of course), and they’re both relatively easy and almost painless.

Below, we’ll dive into the differences between weight loss pens versus syringes, how to use them, which drugs are available in each, and how to choose the best one for you.

To start, here’s a side-by-side comparison.

Pens and syringes are both subcutaneous injections — that is, injections delivered into the skin, not a vein or muscle. Whichever you use, you inject the medication into your upper arm, thigh, or stomach.

When used correctly, they’re both effective, but there are a few key differences.

Weight Loss Pens

Weight loss pen injections are devices pre-filled with medication. They have a needle on one end and a button on the other that delivers the medication through the needle.

You don’t need to measure out a dose of the medication yourself. Some pre-filled pens are single-use, containing just one dose of medication. With these, you won’t need to attach or remove a needle or select your dose.

Some pens contain several doses of medication. With these, you need to attach a new needle with each injection and select your dose of medication on the pen.

For some people, injector pens are easier to use and less intimidating than syringes, especially if you’ve never used injectable medication before. There’s also less chance of giving yourself the wrong dose, as you’re selecting the dose on the pen rather than measuring it out yourself.

Injector pens are a little easier to travel with than syringes and vials, and some can be kept at room temperature once opened.

One downside of single-use pen users? Single-use disposable pens cause more waste than multi-dose pens and syringes.

Weight loss drugs available in single-use injector pens include:

• Wegovy

• Mounjaro

• Zepbound

Weight loss drugs available in multi-dose pens include:

• Ozempic

• Saxenda

• Victoza

• Generic or compounded liraglutide

Your prescribing healthcare provider will go over your options and let you know what might be best for your needs, budget, and lifestyle.

Weight Loss Syringes and Vials

Weight loss medications delivered with syringes are a little trickier than pens, but you’ll most likely get the hang of them after a few goes.

You’ll have a vial of medication and a syringe with a needle. You’ll draw medication from the vial into the syringe, measuring the dose yourself. Then you inject the medication in a similar way to the pen — there’s just a little more preparation needed.

Also, since you’re measuring your own dose, there’s more room for error. But you can avoid this by taking your time and double-checking your dosing.

Weight loss drugs delivered with syringes include:

• Compounded semaglutide

• Compounded tirzepatide

• Generic or compounded liraglutide

Compounded and generic medications can be more affordable and available than brand-name meds. The dosing of compounded drugs can also be personalized to suit individual needs.

Using a weight loss injection pen or syringe is quick, easy, and pain-free. Your prescribing healthcare provider can give you step-by-step instructions for your exact medication, but here’s an idea of what to expect.

How to Use a Single-Use Weight Loss Pen

Single-use pens are the easiest of all delivery systems because there’s no pen needle prep or dose selection required.

Here’s how you use them, using Wegovy as an example:

1. Wash your hands with soap and warm water.

2. Make sure the injection pen isn’t broken and check that the medication is clear, colorless, and particle-free.

3. Clean the injection site with an alcohol swab or soap and water. Let it dry.

4. Remove the pen cap.

5. Push the pen firmly into your skin. Keep applying pressure until the yellow bar on the side of the pen has stopped moving. This should take about five to 10 seconds.

6. Lift the pen slowly away from your skin. Safely discard the pen in a sharps container (or another hard plastic container that can’t be pierced by a needle).

If you’re injecting Mounjaro or Zepbound, you need to unlock the pen before use. To do this, place the base of the pen device against your skin, and turn the lock ring to unlock. Then, press and hold the injection button on top of the pen for 10 seconds to deliver the dose.

How to Use a Multi-Dose Weight Loss Pen

Here’s how to use a multi-dose injection pen, using Saxenda or generic liraglutide as an example:

1. Wash your hands with soap and water.

2. Check that the medication is clear, colorless, and particle-free.

3. Attach a new needle. Do this by removing the needle from its outer packaging and pushing it onto the end of the pen, twisting until it’s on tight. Remove the outer needle cap and inner needle cap.

4. Check the flow. You’ll only need to do this step the first time you use each pen.  Twist the dose selector on the end of the pen until it shows the flow check symbol. Hold the pen with the needle facing up. Push the dose button on the end of the pen until the dose counter shows zero. You should see a drop of medication on the end of the needle.

5. Select your dose with the dose selector. (Your dose will probably start low and gradually increase in small increments each week. Your prescribing healthcare provider will let you know which dose to use and when to increase it.)

6. Insert the needle into your skin, and press and hold the dose button until the dose counter shows zero. Keep holding and slowly count to six.

7. Carefully remove the needle from your skin.

8. Remove the needle from the pen and safely discard it in a sharps container or hard plastic container.

9. Replace the pen cap and put your pen back in the fridge or a safe place.

See our guide on how to use a liraglutide pen for more detailed instructions.

Weight loss syringes take a little more time to prepare and can be intimidating at first. But with practice, they only take a few minutes to administer, and you’ll find they’re not as scary as they look.

Here’s how to prepare the syringe:

1. Wash your hands with soap and warm water.

2. Take the cap off the medication, wipe the top of the vial with an alcohol swab, and remove the cap from the syringe and the needle.

3. Pull back the plunger to the same volume as your prescribed dose to draw air into the syringe.

4. Puncture the top of the vial and push the air into the vial.

5. Hold the vial and syringe upside down with one hand. With the other hand, slowly pull the plunger back to withdraw the medication to your dose.

6. Remove the needle from the vial and lightly tap or flick the syringe to move any air bubbles to the top. Gently push the plunger to remove them. (You may need to add a little more medication if you’ve removed a lot of air.) Double check you’ve got the right dose in the syringe.

Once your injection is ready, here’s how to self-inject it:

1. Hold the syringe between your index finger and middle finger, with your thumb on the plunger. (You can pinch a section of skin if that makes it easier to insert the needle.)

2. Slowly insert the needle into your skin.

3. Gently push the plunger down until it meets the bottom and all of the medication has been injected.

4. Gently remove the needle from your skin and safely discard it.

5. Place the vial back in the fridge.

Check out our guide on how to inject semaglutide for more in-depth instructions.

When considering your options with weight loss injections, pen versus syringe is just one choice you need to make.

The best delivery method for you will depend on:

• Your feelings about needles

• Your feelings about selecting or measuring the dose on your own

• The medication that’s best for you

Here’s what we mean.

Your Feelings About Needles

If you’re scared of needles, using a syringe and vial may feel more intimidating than an injection pen. If you’re terrified of needles, a single-use pen means you don’t need to attach and remove a needle at all, so this may be the best option for you.

However, many folks with a fear of needles can overcome the fear and go on to use injectable medications confidently — even those with syringes and vials!. Syringe users often state how small the syringe needle is and how painless the process is.

Your Feelings About Dosing Accuracy  

There’s no dose selection or measuring required with a single-use pen, making it the simplest, quickest, and most convenient option — and the one with the most dosing accuracy.

A multi-dose pen requires you to select the dose each time you inject. And with a syringe and vial, you’ll need to measure the dose yourself into the syringe.

Depending on your confidence level, you may prefer to not have to measure out a dose yourself. However, the process is simple and you’ll probably get used to it after a few tries — so don’t let this put you off if the medication is right for you.

Your Medication Choice

Wegovy, Mounjaro, and Zepbound come in single-use pens. Ozempic, Victoza, Saxenda, and compounded and generic liraglutide come in multi-dose pens. Compounded GLP-1s and generic liraglutide come in vials with syringes. So, depending on the medication you’re considering, the delivery method will change.

Patient preference is, of course, important. But all types of injections are easy to learn and self-administer, so you’re better off going for the medication that’s best for you in terms of your weight and health profile. Other factors, like affordability and availability, may also come into play.

You don’t have to figure this all out alone, though. A healthcare provider can help you find the best weight loss medication for your unique needs.

Both weight loss pens and syringes are effective, and they’re both relatively quick, easy, and painless once you get the hang of things.

Here are some final points to keep in mind when comparing pens versus syringes: 

• Consider ease of use and the dose-measuring process. Single-use pens are easiest, followed by multi-dose pens, and then syringes. All delivery methods are simple after a few tries, but consider how you feel about measuring your own dose and handling a small needle.

• Consider the best medication for you. Weight loss needles and dose-measuring fears are valid, but don’t let them stop you from improving your health and quality of life with the right medication for you. A healthcare provider will talk through how to administer your injection. You’ll grow more confident with practice, whichever method you choose.

• Look into oral weight loss drugs. If you’re really not a fan of needles (who is, TBH?), there are oral weight loss and diabetes medications that don’t require an injection at all to control appetite or manage glucose (blood sugar). You can check out our custom oral weight loss kits if this is something on your radar.

If you’re looking into your options, you can also take our free online weight loss assessment. Using your answers, a healthcare provider can recommend the best treatment plan for you.