Mounjaro (Tirzepatide) in Singapore: Complete Guide to This Weight Loss Treatment

If willpower worked, you would not be reading this

You have done the calorie counting. You have pushed through the low-carb weeks. You have tracked every meal, forced yourself to the gym when you had nothing left to give, and watched the scale barely move — or worse, watched it creep back up after months of discipline.

If you are reading about Mounjaro in Singapore, you have probably already tried the willpower route more than once. And here is the thing worth knowing: the reason those approaches did not stick has less to do with discipline and more to do with biology. Your body has hormonal systems designed to resist sustained weight loss — systems that increase hunger, slow your metabolism, and push your weight back to where it started.

Tirzepatide, the active ingredient in Mounjaro, works by targeting those systems directly. It is a newer class of weight loss treatment that acts on two hormonal pathways instead of one, and clinical trials show it producing stronger weight loss results than any previously available medication in this category.

This guide covers what tirzepatide is, how it differs from existing GLP-1 medications like semaglutide, what the clinical evidence shows, who qualifies, what it costs in Singapore, and how to talk to your doctor about whether it might be right for you.

What is Mounjaro (tirzepatide)?

Mounjaro is the brand name for tirzepatide, a medication developed by Eli Lilly. It was originally approved for managing Type 2 diabetes, but its weight loss effects have made it one of the most discussed medications in this space. In clinical trials, it produced more weight loss than any other GLP-1 medication tested to date.

Tirzepatide belongs to a new class of medication called a dual incretin agonist, sometimes referred to as a "twincretin." While most GLP-1 medications activate a single receptor (the GLP-1 receptor), tirzepatide activates two: the GLP-1 receptor and the GIP receptor (glucose-dependent insulinotropic polypeptide).

Both GLP-1 and GIP are hormones your body naturally produces in the gut after eating. They play different but complementary roles in regulating appetite, blood sugar, and how your body processes fat. By targeting both pathways simultaneously, tirzepatide produces effects that are stronger than either receptor alone.

Mounjaro is administered as a weekly subcutaneous injection using a pre-filled pen, similar to other injectable GLP-1 medications. The injection goes just under the skin, typically in the abdomen, thigh, or upper arm.

Eli Lilly also markets tirzepatide under the brand name Zepbound, which is specifically approved for weight management in some markets. Mounjaro and Zepbound contain the same active ingredient at the same doses — the difference is the approved indication.

How tirzepatide differs from semaglutide

If you have been researching GLP-1 medications, you have likely come across semaglutide — the active ingredient in Ozempic and Wegovy. Understanding the difference between semaglutide and tirzepatide comes down to one key distinction: single versus dual action.

Semaglutide: single receptor

Semaglutide activates only the GLP-1 receptor. This triggers appetite suppression in the brain, slows gastric emptying so you feel full longer, and improves blood sugar regulation. These are powerful effects — the STEP 1 trial showed 14.9% mean body weight loss at 68 weeks.

Tirzepatide: dual receptors

Tirzepatide was engineered from the human GIP peptide and activates both the GLP-1 and GIP receptors. The GLP-1 effects are similar to semaglutide: appetite suppression, delayed gastric emptying, and glucagon suppression. But the addition of GIP receptor activation adds another layer:

• Improved insulin sensitivity — GIP signalling helps the body use insulin more effectively
• Adipose tissue signalling — GIP receptors are present in fat cells, and activation may influence how the body stores and processes fat
• Stronger combined effect — the two pathways appear to amplify each other, producing greater weight loss than either receptor achieves alone

This dual mechanism is what sets tirzepatide apart from other GLP-1 medications. It works through a different pharmacological approach, not just a higher dose of the same type of drug.

Clinical evidence: the SURMOUNT trials

Tirzepatide has produced the largest weight loss numbers of any obesity medication tested in clinical trials. The key data comes from the SURMOUNT trial programme.

SURMOUNT-1 results

The SURMOUNT-1 trial (Jastreboff et al., New England Journal of Medicine, 2022) enrolled adults with a BMI of 30 or above (or 27+ with at least one weight-related condition) but without Type 2 diabetes. Participants received tirzepatide or placebo for 72 weeks.

Results by dose:

At the highest dose (15 mg), 39.7% of participants lost 25% or more of their body weight (efficacy estimand). To put that in perspective, a person weighing 85 kg would lose roughly 21 kg at the 15 mg dose.

A note on the numbers: the commonly cited "22.5% weight loss" refers to the efficacy estimand, which measures results among participants who stayed on treatment. The intention-to-treat (ITT) figure — which includes everyone enrolled, regardless of whether they completed the study — is 20.9%. Both are large; the ITT number is more conservative.

Metabolic improvements beyond weight loss

SURMOUNT-1 also showed improvements in metabolic health markers:

• Triglycerides reduced by approximately 20-25%
• Systolic blood pressure reduced by approximately 6-8 mmHg (placebo-adjusted)
• Diastolic blood pressure reduced by approximately 4.2 mmHg

These improvements matter because they reduce cardiovascular risk beyond what the weight loss itself accounts for.

How does this compare to semaglutide?

The STEP 1 trial showed semaglutide producing 14.9% mean body weight loss at 68 weeks. SURMOUNT-1 showed tirzepatide at 15 mg producing 20.9-22.5% at 72 weeks. That is roughly 40-50% more weight loss with tirzepatide.

One caveat: no head-to-head trial has been completed yet. SURMOUNT-5, a direct comparison between tirzepatide and semaglutide, is ongoing. Until those results are published, cross-trial comparisons should be interpreted carefully, since differences in trial design, populations, and protocols make direct comparison imperfect. That said, the gap is large enough that most clinicians consider tirzepatide the more potent option for weight loss.

Availability in Singapore

Mounjaro's availability in Singapore is more limited than semaglutide-based medications like Ozempic.

Tirzepatide has received regulatory approval in several markets, including the United States (FDA) and Europe (EMA), for both Type 2 diabetes (as Mounjaro) and weight management (as Zepbound). In Singapore, access depends on the current HSA (Health Sciences Authority) registration status, which can change as Eli Lilly progresses through the local regulatory process.

Because tirzepatide is newer to the Singapore market than semaglutide, not all clinics carry it. Some doctors may be able to prescribe it through special access pathways or through clinics that source it from approved international suppliers. Availability is changing, so it is worth checking with your doctor for the latest status.

If tirzepatide is not yet accessible through your preferred provider, semaglutide-based options like Ozempic and Wegovy are proven alternatives. Many patients do well on semaglutide. The STEP 1 trial showed 14.9% weight loss, and the medication has a longer track record in Singapore.

The most practical approach is to discuss your options with a doctor who is current on what is available and can recommend the best medication for your individual situation.

Zepbound vs Mounjaro: what is the difference?

If you have been searching for Zepbound in Singapore, here is what you need to know: Zepbound and Mounjaro contain the exact same active ingredient — tirzepatide — at the same doses, made by the same manufacturer (Eli Lilly). The only difference is the approved indication.

• Mounjaro was approved for managing Type 2 diabetes
• Zepbound was approved specifically for weight management

In the United States, both brands are available separately. In Singapore, tirzepatide is prescribed under the Mounjaro brand name. Zepbound is not separately registered or marketed here. This means if you are looking for Zepbound in Singapore, your doctor would prescribe the same molecule under the Mounjaro name.

The clinical results are identical because the medication is identical. The SURMOUNT-1 weight loss trial data (20.9% weight loss at 15 mg over 72 weeks) applies regardless of which brand name appears on the packaging.

From a practical standpoint, you do not need to choose between Mounjaro and Zepbound in Singapore — the distinction is a regulatory and marketing one, not a medical one. What matters is whether tirzepatide is appropriate for your health profile, which your doctor can assess during a consultation.

Who qualifies for tirzepatide treatment

Eligibility for tirzepatide follows the same general framework as other GLP-1 weight loss treatments in Singapore.

MOH clinical practice guidelines

Singapore's MOH pharmacotherapy thresholds for weight management are:

• BMI 30 or above without comorbidities
• BMI 27.5-29.9 with at least one weight-related condition (Type 2 diabetes, hypertension, dyslipidaemia, etc.)

These thresholds are lower than Western guidelines because Asian populations face higher metabolic risk at lower BMI levels.

Who should not take tirzepatide

Tirzepatide is contraindicated in the following cases:

• Pregnancy — discontinue at least two months before planned pregnancy
• Breastfeeding — not recommended due to insufficient safety data
• Personal or family history of medullary thyroid carcinoma (MTC) — a rare form of thyroid cancer accounting for 3-4% of thyroid cancer cases
• Multiple Endocrine Neoplasia syndrome type 2 (MEN 2)

Your doctor will review your full medical history during the consultation to confirm you are a suitable candidate. If you have a history of pancreatitis, severe gastrointestinal disease, or certain other conditions, your doctor will weigh the risks and benefits with you.

Dosing schedule

Tirzepatide follows a gradual dose escalation to minimise side effects and help your body adjust. The titration schedule is slower than semaglutide, with more available dose increments.

Available doses: 2.5 mg, 5 mg, 7.5 mg, 10 mg, 12.5 mg, and 15 mg.

Not everyone needs to reach the maximum 15 mg dose. Your doctor will adjust based on your response and tolerability. Some patients achieve their target weight loss at 10 mg or 12.5 mg and stay there. The dose increases happen every four weeks, giving your body time to adapt at each level before moving to the next.

Each dose comes in a single-use, pre-filled injection pen. You inject once per week on the same day each week.

Side effects

Tirzepatide's side effect profile is similar to other GLP-1 medications. Most side effects are gastrointestinal, tend to be mild to moderate, and typically improve as your body adjusts over the first few weeks at each dose level.

Common side effects

• Nausea — the most frequently reported side effect, especially during dose increases
• Diarrhoea — usually mild and temporary
• Reduced appetite — often seen as a therapeutic effect rather than a side effect
• Constipation — can occur, particularly at higher doses
• Vomiting — less common than nausea, more likely during titration
• Abdominal discomfort — including bloating and indigestion

Less common but important

• Injection site reactions — redness, itching, or swelling at the injection site
• Gallbladder events — rapid weight loss with any method can increase the risk of gallstones
• Pancreatitis — rare but serious; seek medical attention for severe, persistent abdominal pain

Managing side effects

The gradual dose titration schedule exists specifically to minimise these effects. Eating smaller, more frequent meals, staying hydrated, and avoiding high-fat or greasy foods can help manage nausea during the adjustment period. Most patients find that side effects become manageable within two to three weeks at each dose level.

Your doctor should be monitoring your response throughout treatment. If side effects are persistent or bothersome, adjusting the dose or extending the titration timeline is a standard approach. For more on what doctors evaluate during treatment, see our guide on what doctors check before prescribing GLP-1.

Cost of tirzepatide in Singapore

Cost is one of the most common questions about Mounjaro in Singapore.

Estimated monthly cost

Tirzepatide generally costs between $600 and $1,200 per month in Singapore, depending on the dose, the prescribing clinic, and whether consultation fees are bundled or charged separately.

The cost varies because:

• Dose escalation — you start at a lower (cheaper) dose and may pay more as you titrate upward
• Clinic pricing models — some clinics charge separate consultation, medication, and delivery fees; others offer all-in pricing
• Supply and sourcing — availability and sourcing affect pricing, particularly for newer medications

How this compares to semaglutide

For comparison, semaglutide-based treatments (Ozempic, Wegovy) in Singapore typically range from $350 to $650 per month. Tirzepatide is generally more expensive. Part of this is its newer status, and part is the additional manufacturing complexity of a dual-agonist molecule.

For a detailed breakdown of GLP-1 treatment costs, see our guide to GLP-1 weight loss costs in Singapore.

Insurance and Medisave

GLP-1 medications prescribed for weight loss are generally not covered by Medisave or standard health insurance in Singapore. There may be exceptions if tirzepatide is prescribed for Type 2 diabetes with co-existing weight management needs, but coverage rules vary by insurer and change frequently. Check with your provider for the latest information.

Mounjaro vs Ozempic/Wegovy: a quick comparison

If you are weighing your options, here is how tirzepatide and semaglutide compare across the most important factors.

Neither medication is universally "better." Tirzepatide shows stronger weight loss results in trials, but semaglutide has a longer track record, is more readily available in Singapore, has wider insurance coverage (for diabetes), and comes in both injectable and oral formulations. The right choice depends on your medical history, treatment goals, budget, and what your doctor recommends.

How to discuss tirzepatide with your doctor

If you are interested in tirzepatide, talk to a doctor who understands the full range of GLP-1 options. A few things that will make that conversation more productive:

Questions worth asking

• Am I a candidate for tirzepatide specifically, or would semaglutide be a better starting point? Your doctor can assess based on your BMI, medical history, and treatment goals.
• Is tirzepatide currently available through your clinic? Availability varies, so it is worth asking directly rather than assuming.
• What is the realistic cost, including consultations and medication? Get the full picture before committing.
• What monitoring do you recommend during treatment? Blood work, weight tracking, and side effect management plans vary by provider.
• What happens if tirzepatide is not available — what is the next best option? Having a backup plan means you can start treatment without delay.

What your doctor will want to know

Be prepared to share:

• Your weight history, including past attempts (diets, exercise programmes, other medications)
• Any existing medical conditions, especially diabetes, heart disease, thyroid issues, or PCOS
• Current medications, including supplements
• Whether you are pregnant, breastfeeding, or planning pregnancy
• Your goals and timeline

A good doctor will not just write a prescription — they will help you understand which medication fits your specific situation, what results to expect, and how to manage the treatment over time.

What is next after tirzepatide?

The weight loss medication field is moving fast. Eli Lilly is also developing retatrutide, a triple receptor agonist that targets GLP-1, GIP, and glucagon receptors simultaneously. In its Phase 3 TRIUMPH-4 trial, the 12 mg dose of retatrutide produced 28.7% weight loss at 68 weeks. It has not been approved yet, with additional Phase 3 trials expected to complete in 2026.

Each generation of these medications has targeted more pathways and produced stronger results. Semaglutide targets one receptor. Tirzepatide targets two. Retatrutide targets three. Whether that translates into a proportional clinical advantage remains to be seen, but the direction is clear.

Frequently asked questions

Is Mounjaro available in Singapore?

Tirzepatide availability in Singapore is more limited than semaglutide-based medications. Access depends on the current HSA registration status and individual clinic supply. Your best step is to ask your doctor directly about current availability and alternative options.

How much does Mounjaro cost in Singapore?

Estimated costs range from $600 to $1,200 per month, depending on dose, clinic, and whether fees are bundled. This is generally higher than semaglutide treatments ($350-650/month). GLP-1 medications for weight loss are typically not covered by Medisave.

Is tirzepatide better than semaglutide for weight loss?

Clinical trial data suggests tirzepatide produces greater weight loss than semaglutide — 20.9-22.5% versus 14.9% — but these are cross-trial comparisons. A head-to-head trial (SURMOUNT-5) is ongoing. "Better" also depends on availability, cost, your medical history, and individual response.

What are the main side effects of tirzepatide?

The most common side effects are gastrointestinal: nausea, diarrhoea, constipation, and reduced appetite. These are typically mild to moderate and improve over time. The gradual dose titration schedule helps minimise discomfort.

Can I take Mounjaro as a pill?

No. Tirzepatide is currently only available as a weekly injection. If you prefer an oral medication, semaglutide is available in pill form as Rybelsus, though the weight loss results with the current oral dose are more modest than injectables.

How long does it take to see results with tirzepatide?

Most patients begin noticing reduced appetite and some weight loss within the first four to eight weeks. Significant weight loss typically develops over several months as the dose is gradually increased. The SURMOUNT-1 trial measured results at 72 weeks.

Is Zepbound available in Singapore?

Zepbound is not separately available in Singapore. Tirzepatide — the active ingredient in both Zepbound and Mounjaro — is prescribed under the Mounjaro brand name here. If your doctor determines that tirzepatide is appropriate for you, you will receive Mounjaro. The medication, doses, and clinical effects are the same regardless of the brand name.

Do I need to diet and exercise while on tirzepatide?

Tirzepatide is not a replacement for healthy habits. Clinical trial participants followed a reduced-calorie diet and increased physical activity. The medication makes it easier to eat less by reducing hunger and food noise, but sustainable results come from combining medication with lifestyle changes.

Individual results vary. The clinical data cited in this article is from published trials with specific populations and protocols. Any medication decision should be made in consultation with a qualified doctor who can assess your individual health profile.