Your guide to Mounjaro
Mounjaro is a treatment that mimics the GLP-1 and GIP hormones to encourage satiation and in turn, promote weight loss.
20% average weight loss in 12 months
Comes in 6 strengths
Administered as a once-weekly injection
Medically reviewed by Kevin J, BSc (Hons)
Last updated 15 July, 2024
Medically reviewed by Kevin J, BSc (Hons)
Last updated 15 July, 2024
What is Mounjaro?
Mounjaro is a medication that encourages weight loss through the combined action of the glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) agonists.

These hormones work to reduce cravings, make you feel fuller for longer and improve blood sugar levels while also aiding fat loss and preventing fat gain. [1]

The active ingredient in Mounjaro, called tirzepatide, is the first dual GLP-1 and GIP receptor agonist and, according to clinical trials, is the most effective weight loss treatment currently available, with an average of 20.9% body weight loss. [2][3]

How GLP-1 and GIP
medications aid weight loss

How Wegovy works for weight loss

Slows digestion and the time it takes to empty the stomach
Reduces appetite and keeps you feeling fuller for longer
Decreases sugar production in the liver, helping to improve fat regulation
Regulates blood sugar levels and increases insulin efficiency

GLP-1 vs GIP

While GLP-1 and GIP target similar areas of the body, these hormones perform different functions to encourage weight loss.

GLP-1
GLP-1
Slows the rate of
stomach empyting
Helps to promote fat
loss
Reduces cravings
Blocks fat gain
Works to speed up your
metabolic rate
Regulates blood sugar
levels
Acts on the pancreas,
GI tract, heart and
brain¹
Acts on the pancreas,
fat, GI tract and brain

How much weight can I lose with Mounjaro?

The weight loss outcomes experienced in clinical trials of Mounjaro are impressive.

A 2022 study of over 2,500 people found that those using GLP-1/GIP treatment lost up to 20.9% body weight after 72 weeks³.

Those weren’t the only heartening findings, with researchers discovering that:

  • Up to 90.9% of people experienced at least 5% weight loss

  • Up to 83.5% were able to achieve a 10% weight loss

  • 56.7% experienced at least 20% weight loss

Mounjaro vs Wegovy for weight loss

Another weight loss injection you’re probably familiar with is Wegovy. And, while it’s often compared to Mounjaro, there are clear differences between these weight loss medications.

While Mounjaro contains the GLP-1 and GIP hormones, Wegovy mimics just the GLP-1 agonist and as a result, the weight loss outcomes differ between the medications. Mounjaro also tends to have fewer side effects for users when compared to Wegovy.

There are currently no published head-to-head trials directly comparing the weight loss medications, but when looking at the respective clinical trials, patients using GLP-1 and GIP treatment achieved 20.9% body weight loss at 72 weeks versus 14.9% body weight loss at 68 weeks for those on GLP-1 treatment.

Although, it’s important to note that Wegovy still delivers excellent weight loss outcomes, but sits just slightly below Mounjaro in projected weight loss.

Weight loss after one
year
20%
15%
Activated hormone
pathways
GLP-1/GIP
GLP-1
Active ingredient
Tirzepatide
Semaglutide
Age eligibility
18-84
18-74
Dosage strengths
2.5mg, 5mg, 7.5mg,
10mg, 12.5mg, 15mg
0.25mg, 0.5mg, 1mg,
1.7mg, 2.4mg
Who is eligible to use Mounjaro?
To access Mounjaro, you’ll need to undergo a prescriber consult, where your healthcare provider can decide if the medicine is right for you.

A few of the eligibility requirements of Mounjaro include:

• You have a body mass index (BMI) of 30 or more, indicating obesity
• You have a BMI of 27 or higher, categorised as overweight, coupled with at least one weight-related health condition such as high blood pressure or type 2 diabetes
What is the dosing schedule for Mounjaro?
Mounjaro injections come in 6 strengths, each in a different colour pen — you work your way from grey to purple, green, pink, blue and end at orange.

You gradually increase your dose every 4 weeks, but you don’t necessarily have to increase to the highest dose if you’re experiencing success at your current strength.

Your prescriber will advise you on increasing your dose and what strength is best for your maintenance dose.
What are the most common side effects of Mounjaro
Side effects are often common when starting a new medication and the same goes for Mounjaro.

The good news is that most of the associated side effects are relatively mild and tend to reduce as your body adjusts to the medication.

Nausea is one of the most common side effects of Mounjaro, with research finding up to 18% of users will experience it.

Diarrhoea can also occur, with clinical trials showing that 1 in 10 people can encounter it while taking Mounjaro. []
The most common Mounjaro side
effects include:
  • Nausea
  • Diarrhoea
  • Vomiting
  • Decreased appetite
  • Constipation
  • Stomach (abdomen pain)
  • Indigestion
  • Bloating
  • Burping
  • Heartburn
Medical weight loss isn’t a shortcut

There’s no shame in turning to weight loss injections to assist you on your weight loss journey. When combined with behavioural and lifestyle changes, you can maintain your healthy weight into the future.

Lilli
15kg
 
Lilli
9.5kg

“My weight would always impact on my sleep apnoea. Since Juniper , I really see the difference.”

Carol Malone
25kg

“Juniper has been my weight loss miracle, we all need help on our weight loss journey, especially because it gets harder the longer it goes on.”

Carol Malone
25kg
Sarah
11kg in 3 months
Sarah
11kg

“Juniper's just given me my confidence back. That's what my friends are saying, “You've got your smile back, you've got your sparkle back,” which I know I'd lost.”

FAQs

How long does Mounjaro take to work?

Everyone responds differently to medication, so the timeline for when you will begin to experience results with Mounjaro can differ.

It’s best to speak to your healthcare provider who will be able to provide you with more personalised advice.

Mounjaro vs Ozempic: What’s the difference?

Mounjaro and Ozempic are both injectable medications that are used to treat type 2 diabetes.

However, Ozempic shares more similarities with Wegovy than Mounjaro, as it’s a GLP-1 medication containing semaglutide.

While Wegovy is licensed for weight management in the UK, Ozempic is licensed for diabetes treatment. Mounjaro, on the other hand, contains the dual GLP-1 and GIP hormones and is used for both diabetes and weight loss treatment.

Mounjaro or Wegovy for weight loss?

In simple terms, Mounjaro delivers higher weight loss percentages than Wegovy, with fewer side effects. In saying that, Wegovy is still an incredibly effective weight loss injection.

Ultimately, it comes down to what your healthcare provider thinks is the best fit for you.

Using Mounjaro

Can I switch from Wegovy to Mounjaro?

Yes! You can move from Wegovy to Mounjaro — it’s generally recommended that you can start GLP-1/GIP treatment 7 days after your last dose of another weight loss medication.

However, if you miss more than 2 doses of the GLP-1/GIP treatment, you’ll need to recommence at a reduced dose to prevent side effects.

Be sure to chat with your healthcare provider as they’ll be able to provide more personalised advice on switching medications.

How long does Mounjaro stay in the body?

The half-life of Mounjaro is approxmately 5 days. So, if you stop using the medication, it should be gone from your body in roughly 30 days. [8]

Remember, the time Mounjaro stays in your body can be different for each person, leading to varying outcomes.

Should Mounjaro be kept in the fridge?

Yes, your medication needs to be kept in the fridge, at a temperature between 2°C to 8°C.

Other Mounjaro storage tips include:

  • Keep the pens in the original packaging to protect from the light
  • Do not freeze the Mounjaro injections
  • Handle with care as the pen has glass parts — if you drop a pen, please don’t use it
  • Ensure your pen isn’t frozen

If your pens have been frozen, exposed to light or temperatures above 30°C, or have been out of the fridge for longer than 28 days, the medication needs to be thrown away.

What if I miss a dose of Mounjaro?

For the medication to be effective, it’s best if you administer it on the same day every week. But, we also know that sometimes life has other plans and you may forget — here’s what to do if that happens.

  • If you miss a dose, take it as possible within 4 days (96 hours) after the missed dose
  • If more than 4 days have passed, skip the missed dose and take your next dose on the regularly scheduled dose [7]

Do not take 2 doses of Mounjaro within 3 days of each other.