Weight Loss Medications in New Zealand — A Complete Guide | KiwiMeds
✅ Reviewed by Ramon Wong, BPharm, Registered Pharmacist (New Zealand) | May 2026 — This information is for educational purposes only and is not a substitute for personalised advice from your doctor or pharmacist. Always seek professional guidance before making changes to your medications.
Weight loss medications (also called anti-obesity medicines or pharmacotherapy for obesity) are prescription drugs that, alongside lifestyle changes, can help people achieve and maintain significant weight loss. In New Zealand, the available options and funded treatments differ from other countries. This guide covers all weight loss medications available in NZ, how they work, and which are funded by Pharmac.
Who is eligible for weight loss medication?
Weight loss medications are generally considered for adults who:
- Have a Body Mass Index (BMI) ≥30 kg/m² (obesity), OR
- Have a BMI ≥27 kg/m² with at least one weight-related health condition (e.g., type 2 diabetes, high blood pressure, sleep apnoea, osteoarthritis)
- Have not achieved adequate results from diet, exercise, and behavioural interventions alone
Medication should always be used as an addition to — not a replacement for — healthy eating and increased physical activity.
Weight loss medications available in New Zealand
The main prescription weight loss medicines currently available in NZ are:
1. Semaglutide (Wegovy / Ozempic)
How it works: GLP-1 receptor agonist — reduces appetite, slows gastric emptying, and increases feelings of fullness. Given as a weekly injection.
NZ availability: Ozempic (2.4 mg weekly) and Wegovy are available on private prescription. Ozempic (lower doses for type 2 diabetes) is funded by Pharmac for people with type 2 diabetes who meet certain criteria — but not funded for weight loss alone.
Expected weight loss: Average of 12–15% body weight in clinical trials (STEP programme) over 68 weeks.
2. Tirzepatide (Mounjaro)
How it works: Dual GIP + GLP-1 receptor agonist — the most effective weight loss injectable currently available. Given as a weekly injection.
NZ availability: Available on private prescription since December 2025 (Medsafe approved). Not funded by Pharmac.
Expected weight loss: Average of 15–22.5% body weight in SURMOUNT trials — the highest weight loss achieved by any pharmacotherapy to date.
Read our full Tirzepatide (Mounjaro) guide →
3. Orlistat (Xenical / Alli)
How it works: Blocks the enzyme (lipase) that digests fat in the gut. Approximately 30% of dietary fat passes through undigested.
NZ availability: Xenical (120 mg) is available on prescription; lower-dose Alli (60 mg) is available over-the-counter. Not funded by Pharmac for weight loss.
Expected weight loss: Average of 3–5% additional weight loss compared to diet and exercise alone. Modest but meaningful for long-term weight management.
Key side effects: Oily/fatty stools, faecal urgency, oily spotting — reduced by following a low-fat diet while taking orlistat.
4. Phentermine
How it works: Stimulant that suppresses appetite by increasing noradrenaline in the brain.
NZ availability: Available on prescription but rarely prescribed due to stimulant side effects, cardiovascular risks, and dependence potential. Not funded by Pharmac.
Limitations: Only approved for short-term use (up to 12 weeks); not suitable for people with heart disease, hypertension, anxiety, or history of drug dependence.
5. Bupropion/Naltrexone (Contrave) — not available in NZ
Contrave (combined naltrexone/bupropion) is approved for weight loss in the US and some other countries but is not registered with Medsafe for this purpose in New Zealand. It cannot be legally prescribed for weight loss in NZ.
Is any weight loss medication funded by Pharmac in NZ?
As of May 2026, no weight loss medications are funded by Pharmac specifically for obesity treatment in New Zealand.
Ozempic (semaglutide at lower doses) is funded for type 2 diabetes management — not primarily for weight loss. If weight loss occurs as a benefit of funded diabetes treatment, that is acceptable, but Pharmac does not fund semaglutide or any other drug specifically as an anti-obesity medicine.
This is a significant access issue. In many comparable countries (including the UK and Australia), some form of weight loss pharmacotherapy is funded for people with obesity and related conditions.
Comparing weight loss medications — which is most effective?
In order of average weight loss effectiveness (from clinical trial data):
- Tirzepatide (Mounjaro) — 15–22.5% body weight loss — most effective available
- Semaglutide (Wegovy) — 12–15% body weight loss
- Orlistat (Xenical) — 3–5% additional weight loss
- Phentermine — 5–10% short-term weight loss; not suitable long-term
Individual results vary significantly. Factors including genetics, diet adherence, and concurrent health conditions all affect response.
Side effects common to weight loss medications
Different medications have different side effect profiles, but common issues include:
- GLP-1 and GIP/GLP-1 agonists (semaglutide, tirzepatide): Nausea, vomiting, diarrhoea, constipation — especially when starting or increasing dose
- Orlistat: Oily stools, flatulence, faecal urgency — managed by eating low-fat meals
- Phentermine: Insomnia, dry mouth, increased heart rate, anxiety, dependence risk
Do weight loss medications work long-term?
An important consideration: most weight loss medications need to be taken indefinitely to maintain results. Clinical data shows that when GLP-1 medications (semaglutide, tirzepatide) are stopped, the majority of patients regain most of the weight within 1–2 years. This is because these medications suppress appetite by pharmacological means, and that suppression ends when the drug is stopped.
This makes long-term cost a significant factor in NZ, where all weight loss medications are paid privately. At current private prices, semaglutide or tirzepatide can cost thousands of dollars per year.
Weight loss medications and surgery — how do they compare?
Bariatric surgery (e.g., gastric sleeve, gastric bypass) remains the most effective long-term treatment for severe obesity, with weight loss of 20–35% typically maintained for many years. However, surgery carries procedural risks and is not suitable for everyone.
Tirzepatide’s weight loss results are now approaching surgical outcomes in some patients, making pharmacotherapy a genuine alternative for people who are not candidates for or do not want surgery.
How to get a weight loss medication prescription in NZ
- Speak to your GP about your weight and health concerns
- Your GP will assess your BMI, medical history, and previous weight loss attempts
- If medication is appropriate, they will discuss options and issue a private prescription
- Some specialist weight management clinics (both public and private) can also prescribe and monitor weight loss pharmacotherapy
Frequently asked questions about weight loss medications in NZ
Can I get Ozempic for weight loss in NZ without diabetes?
You can get a private prescription for semaglutide for weight loss, but it will not be funded by Pharmac unless you also have type 2 diabetes and meet the funded criteria.
Is Wegovy available in New Zealand?
Wegovy (semaglutide 2.4 mg for obesity) has some market presence in NZ as a private prescription option. Ozempic (same molecule, different doses for type 2 diabetes) is also available. Check with your doctor and pharmacy about current availability and cost.
Are there any natural or over-the-counter weight loss options?
Lower-dose orlistat (Alli 60 mg) is available without prescription at NZ pharmacies. Other OTC “weight loss” supplements have very limited or no evidence of effectiveness and are not recommended as a primary treatment for obesity.
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