Mounjaro (Tirzepatide): Raising the Bar for GLP-1 Treatments

In our previous article we talked about GLP-1 agonists. In this follow-up, we’re going to look specifically at tirzepatide, one of the more recent and most popular GLP-1 agonists.

A little refresher on GLP-1

What is a GLP-1 agonist?

We covered this in great detail in our previous article, so we won’t do a deep dive here. 

But here’s the general idea.

A GLP-1 agonist mimics the naturally occurring GLP-1, a hormone released in the gut after you eat.

GLP-1 helps to keep blood sugar stable (that’s not all it does, but for the purpose of this article, that’s our focus).

GLP-1 agonists are often prescribed by doctors to patients with type 2 diabetes.

And because GLP-1 agonists quiet food noise, they’ve become super popular for those on a weight loss journey.

Now let’s talk about tirzepatide.

What is tirzepatide?

Tirzepatide is one of the most popular GLP-1 agonists.

It’s marketed under the brand names of Mounjaro (used for type 2 diabetes in the US, and for both type 2 diabetes and weight management in the UK) and Zepbound (used for weight management in the US). It’s administered as a once-a-week injection that you can do yourself

Tirzepatide requires a doctor’s prescription.

Like other GLP-1 agonists, doctors most often prescribe it for patients with diabetes. But it can be prescribed for weight loss if you meet the requirements.

In the UK and the US, that means a BMI of 30 or more, or 27 if you also have a weight-related condition like high blood pressure or type 2 diabetes.

What makes tirzepatide different from other GLP-1 agonists?

What really sets tirzepatide apart from the others is that it is a dual agonist.

Tirzepatide mimics not only GLP-1, but also GIP, another hormone released in the gut in response to food.

Most other GLP-1 agonists, such as semaglutide (Ozempic), only target the GLP-1 receptor.

Tirzepatide’s dual action means that it is super effective in regulating blood sugar levels and controlling appetite.

And it’s been shown to produce greater weight loss results than other GLP-1 agonists.

How does tirzepatide work?

Here’s a breakdown:

Increases insulin

When you eat, tirzepatide stimulates an insulin response.

This moves glucose into your cells, lowering blood sugar levels in the bloodstream.

Lowers glucagon

Glucagon is a hormone that basically tells the liver to make more sugar.

Tirzepatide reduces glucagon.

Slows gastric emptying

Tirzepatide slows down the movement of food, so blood sugar levels are more stable, and you stay full longer.

Please note - because it slows digestion, it can also affect how some medicines are absorbed. If you take the pill for birth control, you’ll need to use another method for 4 weeks after starting and after each time you increase your dose.

Regulates appetite

Tirzepatide acts on appetite receptors in the brain and reduces cravings.

This is where the “no more food noise” magic comes in.

Improves insulin sensitivity

Tirzepatide helps the body use insulin more efficiently.

Helps the body burn fat

Most of the fat loss comes from eating less because of reduced appetite, but the GIP part of tirzepatide may also help the body handle fat and insulin better.

Does tirzepatide have side effects?

Like any medication, and like all GLP-1 agonists, tirzepatide can have side effects.

They often occur when you first start tirzepatide, or when you increase your dosage, and usually improve with time.

Common side effects include:

Gastrointestinal Issues - This is the most common side effect, including constipation, cramps, diarrhea, nausea, vomiting, heartburn, and belching

• Fatigue

• Dizziness

• Allergic reactions, such as itching or rashes

• Injection site reactions (redness, swelling)

Rare and more serious side effects can include:

• Pancreatitis

• Gallbladder issues

• Thyroid tumours

• Kidney problems

• Severe allergic reactions such as difficulty breathing and swelling of the face, lips, or throat

• Diabetic retinopathy

• Severe changes in mood or behaviour

Please note that the more serious side effects are very rare. Here are some stats:

Pancreatitis – is seen in about 0.2% of people in studies, which is similar to people not taking the drug, but it’s still a known risk so it’s taken seriously.

Gallbladder issues – uncommon, around 0.6% in one big study, but rapid weight loss of any kind can sometimes be the cause.

Kidney problems – very rare, and usually only in people who already have kidney issues. In fact, tirzepatide might even help protect the kidneys in some cases.

Thyroid tumours – While animal studies have shown this risk, human trials haven’t confirmed it.

Severe allergic reactions – very rare, about 0.1% of people in studies.

Diabetic retinopathy – rare, but people who already have diabetic eye disease should be monitored because big drops in blood sugar can sometimes make it flare up at first.

Mood or behaviour changes – low incidence, with only 1.2% of total safety reports for GLP-1 agonists. It’s worth noting that weight loss and changes in diet can also play a role in mood changes.

As always, it’s important to check in with your doctor if you experience any side effects while using tirzepatide.

Do I need to change my diet if I’m using tirzepatide?

Tirzepatide is a powerful tool. But, like all of the GLP-1 agonists, it is not magic.

It won’t wipe out a bad diet.

In fact, many of those common side effects seem to only happen when people use tirzepatide but still have the same bad eating habits.

Tirzepatide is meant to be used in conjunction with smart diet choices.

And by smart, we mean a whole foods diet.

One that focuses on healthy fats and proteins, and low-carb vegetables and berries.

But what tirzepatide will do is quieten food cravings, and that can help you make those better food choices.

Who should not take tirzepatide for weight loss?

Your doctor will know whether or not tirzepatide is safe for you.

Having kidney or liver problems doesn’t always mean you can’t take it, but you’ll need closer monitoring, especially if you get severe sickness or dehydration.

Obviously not children or anyone who is pregnant or breastfeeding.

Tirzepatide also comes with a boxed warning:

Tirzepatide is contraindicated in patients with medullary thyroid cancer. Tirzepatide is also contraindicated in multiple endocrine neoplasia syndrome type-2 (MEN-2).

It’s also not advised for people with severe stomach emptying problems (gastroparesis), because it hasn’t been studied in this group.

One more thing about tirzepatide

Once you start taking tirzepatide (or any GLP-1 agonist), you will need to continue it in order to keep getting the benefits.

If you stop using tirzepatide, your weight loss will likely slow down (or stop), and your food noise will return.

Studies have shown that many people regain a lot of the lost weight within months of stopping, especially if they go back to old eating patterns.

It’s important while you’re taking tirzepatide that you use this time to heal your relationship with food.

Tirzepatide is a tool that can help you reach your weight loss goals, it is not a license to eat poorly.

Summary

Tirzepatide is a powerful dual agonist that promotes stable blood sugars and appetite correction.

In conjunction with healthy eating habits and exercise, tirzepatide can empower you in your weight loss journey.