Type 2 diabetes remains a significant public health challenge in the United States. As a result, many drug manufacturers have scrambled to produce medications to control and treat this life-changing healthcare condition. Eli Lilly, for example, has introduced two FDA-approved drugs, Mounjaro and Trulicity. Both of which, act as receptor agonists to control an individual’s blood sugar levels. However, the exact mechanisms of these two drugs are different. In this article, we will explore major differences, including the drugs’ mechanism of action and the conditions they have been approved to treat.

What is Mounjaro?

Mounjaro is a recently FDA-approved injectable medication designed to help treat and control symptoms for adults with type 2 diabetes. This medication works by reducing an individual’s A1C blood glucose levels. It joins several other type 2 diabetes drugs that have recently emerged on the market following FDA approval. However, it acts in a different manner, working directly on both GIP and GLP-1 pathways.

How Does Mounjaro Work?

Like with many other diabetes medications, initial results for Mounjaro have been extremely promising. In fact, some studies have shown that up to 90% of patients on a 10 mg dose of Mounjaro have been able to bring their A1C levels under 7 percent. Even individuals who take lower doses of this medication have seen improved blood glucose levels. These impressive results leave many wondering how the drug is so effective.

Most type 2 diabetes drugs on the market, like Ozempic and Wegovy, are single-receptor agonists. Mounjaro, on the other hand, is a dual receptor agonist acting on both GIP and GLP-2. These receptors are directly involved in controlling blood sugar levels and signaling to a person if they are hungry or full. Because it acts on two receptors, it may offer more bang for the proverbial buck than single-receptor agonist drugs.

As many medical professionals note, Mounjaro is an entirely new class of drugs.

Mounjaro Dosage

Like many type 2 diabetes medications, Mounjaro also follows a ramped dosing approach. Initially, individuals receive a 2.5 mg injection once a week. After four weeks on this loading dose, they’ll go up to a 5 mg injection each week. This 5 mg dose may be enough for some to control their blood sugar levels. However, if it’s not, one’s doctor may increase their dose to a 7.5 mg injection each week after a month at the 5 mg dose. Doses can be ramped up even further, going to 10 mg, 12.5 mg, or even 15 mg per week. It’s important to work directly with your provider to ensure that the dose you are on works best for you.

What is Trulicity?

Trulicity is an earlier type 2 diabetes drug introduced by Eli Lilly and approved by the FDA in 2014 following impressive clinical study results. Dulaglutide, a single agonist-receptor, acts directly on GLP-1 to reduce an individual’s blood sugar levels. It has also been shown to lead to dramatic weight loss in many individuals, even though it has not yet received FDA approval as a weight loss medication.

In addition to being approved for those with type 2 diabetes, it addresses cardiovascular disease for people with elevated risk factors, such as age, high blood pressure, high cholesterol levels, and smoking history. This is critical because type 2 diabetes and cardiovascular disease are often co-morbid conditions.

How Does Trulicity Work?

Trulicity effectively lowers blood glucose levels in individuals with type 2 diabetes by binding to receptor cells in the pancreas. These receptor cells are responsible for producing insulin. For most people with type 2 diabetes, these cells don’t function as well as they should, and insufficient insulin is produced. Trulicity stimulates insulin production, which in turn lowers blood glucose levels.

In addition to acting through this mechanism, Trulicity also increases how long food stays in a person’s stomach. By delaying gastric emptying, it helps prevent rapid blood sugar spikes that often happen after meals. Trulicity is also a known glucagon blocker, and this helps reduce blood sugar levels.

Trulicity Dosage

To start, both pediatric and adult patients receive a 0.75 mg subcutaneous injection for at least four weeks. This dosage is then increased to 1.5 mg per week to achieve optimal glycemic control in adults. After four weeks at this dosage, the dosage can continue to be ramped up to a maximum of 4.5 mg per week injection if someone is still symptomatic.

Many pediatric patients are maintained at the initial dosage of 0.75 mg per week. However, increasing the dose to 1.5 mg per week after four weeks of the loading dose is possible if a pediatric patient doesn’t have glycemic control.

The Application Method For Mounjaro and Trulicity

Both Mounjaro and Trulicity are delivered as subcutaneous injections via injectable pens. While many don’t like injectable pens, these are very easy to use. In fact, most people report little to no discomfort with these injections. Most individuals inject themselves in their thighs, upper arms, or abdomen. However, some may prefer having a friend or loved one deliver the shot. Most medical professionals recommend that individuals rotate where they are giving their shot.

Average Weight Loss in Clinical Trials

Even though Mounjaro hasn’t yet been approved as a weight loss medication, clinical trials suggest that many individuals on Mounjaro have reported significant weight loss on the drug. With Mounjaro, the amount of weight loss seems to be tied directly to the dosage people take. For example, people on the maximum 15 mg weekly injection have reported losing up to 21% of their body weight.

During 26 and 52-week clinical trials of Trulicity, participants reported weight losses ranging from roughly 6 pounds to just over 10 pounds. As with Mounjaro, higher doses of Trulicity seem to be linked to more rapid and dramatic weight loss.

Drug Interactions

With any medications, it’s vital that individuals are aware of any potential drug interactions and take steps to protect their health. Mounjaro may interact with insulin medications, including sulfonylurea or insulin secretagogue. It may interact with oral hormonal contraceptives as well.

There is also a long list of medications that Trulicity may interact with. Some of these drugs overlap with the Mounjaro interactions, such as diuretics, corticosteroids, nicotinic acid, estrogens, and calcium channel-blocking agents. These interactions can range from severe and life-threatening ones to more moderate interactions.

In addition, because Trulicity can change how long medications may remain in your stomach before emptying into your intestines, it can also alter medication absorption levels.

Given these potential interactions, one needs to be fully transparent with their medical providers about the medications and supplements they take. Also, individuals should immediately report any concerning symptoms to their medical team.

Common Side Effects of Mounjaro and Trulicity

Although type 2 diabetes drugs are meant to help individuals improve their quality of life, this doesn’t mean that the drugs don’t have potential downside risks.

Both Mounjaro and Trulicity have side effects that closely mirror each other. The most common side effects people experience are GI in nature. These may include diarrhea, nausea, vomiting, and constipation. Some people will also notice a dramatic decline in their appetite.

There are also more serious but less common side effects associated with the medications. For example, people who take Mounjaro or Trulicity may have an elevated risk of developing cancerous thyroid tumors. There is also a high risk of developing pancreatitis and severe kidney complications.

If you develop adverse symptoms from type 2 diabetes, it’s essential to know that stopping the drug may not immediately stop these symptoms as these drugs have a half-life of 5 days. This means it can take up to 30 days for your body to eliminate the drug from your system entirely.

Making Informed Treatment Decisions

Trulicity and Mounjaro are both FDA-approved type 2 diabetes drugs produced by Eli Lilly that have shown impressive results in controlling one’s A1C levels. Even though they both act as agonists on key receptors, several factors set the two drugs apart. Trulicity is a single agonist, whereas its newer cousin drug, Mounjaro, is a dual agonist receptor, which may mean increased results.

Another factor that sets apart these drugs is that, at present, Mounjaro is only approved for type 2 diabetes. However, there is a push for it to be considered as an approved weight loss drug. Although Trulicity isn’t approved for weight loss either, it’s approved for cardiovascular disease treatment.

If you’re struggling with type 2 diabetes, consult with your medical provider to see if these medications would be appropriate for your condition.

Mounjaro

Trulicity

Generic nameTirzepatideDulaglutide
Manufacturer Eli Lilly & Co.Eli Lilly & Co.
UsesUse to treat adults with type 2 diabetes as an adjunct to diet and exercise.To improve glycemic control in children 10 years of age and adults with type 2 diabetes mellitus.
FDA-ApprovalMay 2022September 2014
Receptor Targets GLP-1 and GIPGLP-1
Dose Range2.5 mg to 15 mg0.75 mg to 4.5 mg
DeliverySubcutaneous injectionSubcutaneous injection
Common Side Effects
  • nausea
  • vomiting
  • constipation
  • decreased appetite
  • vomiting
  • diarrhea
  • stomach pain
  • constipation
  • reduced appetite