Mounjaro vs. Trulicity: 6 Differences Between These Diabetes Injections

If you’re living with Type 2 diabetes, you’re likely taking medication to help lower your blood glucose (sugar). Oral medications are a common starting point for many people. But it’s also common to use diabetes injections. This is especially true if your treatment goals include weight loss or heart protection.

Mounjaro (tirzepatide) and Trulicity (dulaglutide) are two popular non-insulin injections. They’re both safe and work well for Type 2 diabetes. But they have some notable differences, including how they work.

Mounjaro vs. Trulicity at a glance

The table below lists notable differences between Mounjaro and Trulicity.

*Mounjaro and Trulicity are not approved for weight management but can cause weight loss as a side effect.

Below are six things to keep in mind when comparing Mounjaro versus Trulicity.

1. Mounjaro and Trulicity work slightly differently in the body

Mounjaro and Trulicity both act like natural gut hormones that help balance blood sugar levels and regulate appetite. But they target slightly different ones.

Mounjaro mimics two hormones:

• Glucose-dependent insulinotropic polypeptide (GIP)

• Glucagon-like peptide-1 (GLP-1)

Trulicity only acts like GLP-1. So that means they’re in different medication classes. Mounjaro is a dual GIP/GLP-1 receptor agonist. And Trulicity is a GLP-1 receptor agonist.

Both medications have similar actions in the body. These include:

• Signaling the pancreas to release insulin when you eat

• Reducing how much sugar your liver makes

• Slowing the passage out food out of your stomach

• Targeting areas of your brain that regulate appetite and food cravings

Because Mounjaro targets two gut hormones, it tends to have a greater effect on blood sugar and weight loss than Trulicity.

2. Mounjaro and Trulicity have different FDA-approved uses

Mounjaro and Trulicity are once-weekly injections that are FDA-approved to treat adults and children ages 10 and older living with Type 2 diabetes. But Trulicity is also approved to lower the risk of serious cardiovascular problems among adults living with Type 2 diabetes and heart disease, as well as those at risk for developing heart disease. Researchers have studied Mounjaro and cardiovascular risk reduction, but the medication isn’t approved for this use yet.

3. Mounjaro comes in more dosage forms than Trulicity

Both Mounjaro and Trulicity are available as single-dose prefilled pens. But Mounjaro also comes as single-dose and multi-dose vials, as well as multi-dose pens (Mounjaro KwikPens). This can offer more flexibility for people using Mounjaro.

Multi-dose vials and pens may also be easier to transport compared to single-use options. These options last longer compared to single-dose options when stored at room temperature. If you’re traveling for a while, you may find it convenient to have fewer items to pack. For example, you may only need to take one Mounjaro KwikPen (and pen needles) with you. But you may need to carry two or more Trulicity pens, depending on how long you’ll be away.

Keep in mind that Trulicity and single-dose Mounjaro pens come ready to use. You’ll need to purchase pen needles separately if you’re using Mounjaro KwikPens. And you’ll need to buy separate syringes and needles if you’re using single-dose or multi-dose Mounjaro vials.

4. Mounjaro may provide greater A1C reduction than Trulicity

In studies, Mounjaro provided greater reduction of hemoglobin A1C (HbA1c or A1C) than Trulicity. Your A1C is an average of your blood sugar levels over the past 2 to 3 months.

A head-to-head clinical trial compared Mounjaro to Trulicity for Type 2 diabetes. After 1 year, those using Mounjaro had between a 2.4% and 2.8% A1C reduction, depending on the dose. Those using Trulicity had a 1.3% reduction.

Keep in mind that this study only compared the 0.75 mg dose of Trulicity to Mounjaro. Higher doses (up to 4.5 mg) weren’t included. But individual studies of Trulicity found that higher doses led to an A1C reduction of up to 1.8% at 8 months. These A1C results were maintained for another 4 months until the study ended. So it’s likely that Mounjaro would still provide greater blood sugar management than Trulicity, regardless of the dose.

5. Mounjaro may provide greater weight loss than Trulicity

Mounjaro and Trulicity aren’t approved for weight loss. But people using these medications tend to lose weight. And you may lose more with Mounjaro than with Trulicity.

The same clinical trial mentioned above also looked at changes in body weight. Those using Mounjaro lost an average of 12 lbs to 24 lbs during the study. Higher doses led to greater weight loss. Participants who used Trulicity lost minimal weight (about 1 lb).

Again, this study only looked at the 0.75 mg dose of Trulicity. But individual studies found that the highest Trulicity dose helped people lose an average of 10 lbs. So it can still provide a significant amount of weight loss for some people.

Good to know: The active ingredient in Mounjaro (tirzepatide) is approved for weight loss under the brand name Zepbound. The active ingredient in Trulicity (dulaglutide) isn’t approved for weight loss under any brand name.

6. Mounjaro may be more likely than Trulicity to cause digestive side effects

Mounjaro and Trulicity both commonly cause gastrointestinal (GI) side effects. These include nausea, diarrhea, and constipation. But studies comparing the two found people using higher doses of Mounjaro (10 mg or 15 mg) experienced these issues more often.

Keep in mind that many people can use Mounjaro or Trulicity without major problems. GI side effects are usually most bothersome when you first start one of them. They can also be more noticeable after raising your dose. But they typically get better or go away after your body adjusts to the medication. Starting with the lowest dose and slowly raising it helps limit GI side effects.

If you’re having trouble with Mounjaro or Trulicity side effects, let your prescriber know. They may suggest a dose change. They can also provide tips to help manage these side effects until your body adjusts.

Can you switch from Trulicity to Mounjaro?

Yes. it’s possible to switch from Trulicity to Mounjaro. In fact, studies suggest making the switch can be helpful if you’re not meeting your diabetes treatment goals with Trulicity. You’ll likely experience additional A1C or body weight reduction.

Keep in mind that there are no standard directions for how to switch between Trulicity and Mounjaro. So be sure to follow your prescriber’s instructions when it comes to what Mounjaro dosage you should start with.

How to save on Mounjaro and Trulicity

There are ways to save on Mounjaro and Trulicity, which are available as brand-name medications. GoodRx can help you navigate between copay savings cards and patient assistance programs to save money on your prescription.

• Save with a copay savings card. If you have commercial insurance, you may be eligible to pay as little as $25 per prescription for Mounjaro or Trulicity using a savings card from the manufacturer.

• Save with patient assistance programs. If you’re uninsured or underinsured, you may be eligible for Trulicity’s patient assistance program, which offers the medication free of cost.

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Written by:

Kristina D. Carter, PharmD, MBA, MHA

Kristina D. Carter, PharmD, MBA, MHA, has over 25 years of experience working in healthcare. She is registered as a licensed pharmacist in Georgia, Indiana, and Tennessee.

Edited by:

Christina Aungst, PharmD

Christina Aungst, PharmD, is a pharmacy editor for GoodRx. She began writing for GoodRx Health in 2019, transitioning from freelance writer to editor in 2021.

Reviewed by:

Alyssa Billingsley, PharmD

Alyssa Billingsley, PharmD, is the director of pharmacy content for GoodRx. She has over a decade of experience as a pharmacist and has worked in clinical, academic, and administrative roles.

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