Mounjaro has long come in the US as a single-dose pen with a hidden, built-in needle. In early 2026, the FDA also approved a multi-dose Mounjaro KwikPen that holds four weekly doses in one device. The KwikPen works differently: you attach a separate needle before every injection, and you need to buy those needles yourself. This guide explains which pen needles for Mounjaro KwikPen fit, what size most adults use, and how many to buy so a missing needle never delays a weekly dose.
Does the Mounjaro KwikPen Come With Pen Needles?
Plan on buying them separately. Lilly doesn't make pen needles, and its KwikPen instructions list a KwikPen-compatible pen needle as a supply that is not included in the carton. That often surprises people switching from the single-dose pen, so it's worth ordering needles at the same time you fill your prescription.
A quick comparison of the US Mounjaro formats:
- Single-dose pen: needle built in. No pen needles needed.
- Multi-dose KwikPen (4 doses): buy pen needles separately, one for each injection.
- Vials: used with syringes, not pen needles.
Which Pen Needles Fit the Mounjaro KwikPen?
The KwikPen uses the standard screw-on connection found on most US insulin and GLP-1 pens. Lilly's own KwikPen FAQ (published for Canada) says the pen works with ISO-standard pen needles from brands such as Embecta (formerly BD), Novo Nordisk, and Terumo, in lengths from 4mm up to 12.7mm. In other words, the needle brand doesn't have to match the pen brand. Check the compatibility list on the needle box and your pen's Instructions for Use, and ask your pharmacist if you're unsure.
Two popular short, thin choices for the Mounjaro KwikPen:
- NovoFine Plus 32G 4mm, 100-count box: Novo Nordisk's shortest, thinnest needle, currently $76.99 (about $0.77 per needle).
- BD Nano 2nd Gen 32G 4mm, 100-count: the same size from BD, with a wider contoured base, currently $76.97.
Prices can change, so check each product page. You can also compare every option in our pen needles for GLP-1 pens collection.
What Size Pen Needle for Mounjaro KwikPen?
Mounjaro is injected under the skin (subcutaneously) into the abdomen, thigh, or upper arm. Widely used injection technique guidance favors short needles, such as 4mm or 5mm, for most adults because they reach the fat layer with less chance of going into muscle.
- Length: 4mm is a common starting point and is usually inserted straight in at 90 degrees.
- Gauge: higher numbers are thinner. 32G is among the thinnest pen needles sold in the US.
- Dose size: moving up to a higher Mounjaro dose doesn't mean you need a longer needle.
- Your provider decides: if you were taught a specific length or technique, keep following it.
How Many Pen Needles Do You Need for Mounjaro KwikPen?
Each KwikPen delivers four weekly doses, and you use a brand-new needle for every injection:
- Per pen: 4 needles, plus a couple of spares for a dropped or bent needle.
- Per month: about 4 to 5 needles.
- Per year: about 52 needles.
A 100-count box can cover well over a year of weekly injections, so check the expiration date and make sure it fits your timeline. Many people with type 2 diabetes also use an insulin pen. If both pens are on the box's compatibility list and your provider is fine with the same length, one box can cover both, and the NovoFine Plus 2-box value pack lowers the cost per needle. Pen needles are generally an eligible FSA/HSA expense; check with your plan administrator.
Mounjaro KwikPen Pen Needle Checklist
- Order pen needles before your first KwikPen dose.
- Peel the paper tab, screw the needle on straight, and remove both the outer cap and the thin inner cap.
- Prime the pen exactly as your Instructions for Use describe.
- After each injection, unscrew the needle and drop it in a sharps container.
- Don't store the pen with a needle attached; it can leak, clog, or let air in.
- Never share your KwikPen with anyone, even with a new needle.
Using Lilly's weight-management version instead? See our guide to pen needles for Zepbound KwikPen.
FAQ
Do Ozempic needles fit the Mounjaro KwikPen?
NovoFine Plus needles, the type packed with US Ozempic pens, use the same standard screw-on connection as Lilly KwikPens. Confirm with your pharmacist if you're unsure.
Can I reuse a needle for next week's dose?
No. Pen needles are single-use. Reusing one can dull the tip, block the needle, and raise infection risk.
Do I need pen needles for the Mounjaro single-dose pen?
No. The single-dose pen has its own built-in needle.
New customers can use code WELCOME10 for 10% off their order.
This article is general information, not medical advice. Follow your healthcare provider's instructions for your medication, dose, needle size, and injection technique.
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