Weight Loss Injections Hong Kong: Ozempic, Mounjaro & Your Options (2026)
Weight Loss Injections Have Changed What's Achievable — If You Choose Carefully
The term "weight loss injections" covers a range of medications, and not all are equal. In Hong Kong in 2026, the most clinically significant options are the GLP-1 receptor agonists — a class of once-weekly injectable medications that produce weight loss through appetite regulation and metabolic effects. The results from clinical trials are substantial enough that they have changed the conversation in obesity medicine globally.
But there is also a wider landscape: older medications with more modest effects, unregulated compounds marketed as weight loss injections, and legitimate supporting treatments (like peptides and IV nutritional therapy) that are sometimes grouped under the same umbrella. Understanding what's what — what works, what's regulated, and what requires clinical supervision — is the first step to making a sensible decision.
This guide covers the main options available in Hong Kong, how they compare, who qualifies, and what a proper clinical programme looks like.
The GLP-1 Receptor Agonists: The Main Event
GLP-1 (glucagon-like peptide-1) receptor agonists are synthetic versions of a gut hormone that regulates appetite, blood sugar, and gastric emptying. They are once-weekly subcutaneous injections that have consistently demonstrated 15–22% body weight reduction in clinical trials — making them far more effective than any previous non-surgical weight management intervention.
Two GLP-1 medications are available in Hong Kong:
Ozempic (semaglutide)
Ozempic is manufactured by Novo Nordisk and contains semaglutide — a GLP-1 receptor agonist that activates appetite-suppressing pathways in the brain, slows gastric emptying, and improves insulin response. It was originally approved for type 2 diabetes and is widely prescribed off-label for weight management in non-diabetic patients.
In the STEP 1 clinical trial, adults with obesity using semaglutide at the weight management dose (2.4mg) lost an average of 14.9% of their body weight over 68 weeks. At the Ozempic 1mg dose used in Hong Kong (Wegovy's 2.4mg formulation is not separately registered here), results are comparable though slightly lower in average.
Ozempic is a once-weekly injection. The pen is pre-filled and straightforward to use after initial instruction. Starting dose is 0.25mg, titrated upward over several months to the therapeutic dose.
Mounjaro (tirzepatide)
Mounjaro, developed by Eli Lilly, is a dual GIP/GLP-1 receptor agonist — it activates both the GLP-1 receptor and the GIP (glucose-dependent insulinotropic polypeptide) receptor simultaneously. This dual mechanism produces a stronger combined hormonal effect than semaglutide alone.
In the SURMOUNT-1 trial, participants using tirzepatide 15mg lost an average of 20.9% of their body weight over 72 weeks — the highest average weight loss recorded in any pharmaceutical trial to date. About a third of participants lost more than 25% of their body weight, outcomes previously only achieved through bariatric surgery.
Mounjaro received regulatory approval in Hong Kong in late 2024 with an on-label weight management indication, making it the first injectable weight management medication with explicit approval for that use in Hong Kong (Ozempic's approval is primarily for diabetes).
Which is better — Ozempic or Mounjaro?
Clinical trial data consistently shows higher average weight loss with tirzepatide. Head-to-head data from the SURPASS-2 trial shows tirzepatide outperforming semaglutide in patients with type 2 diabetes; indirect comparisons in weight management trials point in the same direction.
However, "better" depends on the individual. Some patients achieve excellent results on semaglutide; tirzepatide is not always better for every person. Cost, tolerance of side effects, and health history all factor into which medication a doctor recommends. The right choice is made at consultation, not in advance.
Other Weight Loss Injections: What They Are and Where They Fit
Older GLP-1 medications (liraglutide / Saxenda)
Liraglutide (Saxenda), a once-daily injectable GLP-1 agonist, was the predecessor to semaglutide in weight management. Its average weight loss (around 5–8% of body weight) is meaningfully lower than semaglutide or tirzepatide, and the daily injection schedule is less convenient. Most doctors prescribing GLP-1 medications for weight management in Hong Kong now use semaglutide or tirzepatide instead, where these are available and appropriate.
HCG injections
Human chorionic gonadotropin (HCG) injections combined with a very low calorie diet (500 kcal/day) were popularised in the 1950s and continue to be marketed in some wellness contexts. The evidence base for HCG as a weight loss agent — as distinct from the severe caloric restriction that accompanies it — is poor. Most weight loss on HCG protocols is attributable to the diet, not the hormone. Regulatory bodies including the FDA have concluded that HCG has no proven benefit for weight loss beyond placebo.
Lipotropic injections (B12, MIC)
Injections containing B12, methionine, inositol, and choline (MIC) are marketed as fat-burning or metabolism-boosting injections. B12 injections have genuine value for patients with B12 deficiency or absorption issues. The fat-burning properties of MIC compounds are not supported by robust clinical evidence. These are at best supportive treatments, not primary weight management interventions.
Peptides for body composition
Peptides such as CJC-1295/ipamorelin (which stimulate growth hormone release) and AOD-9604 (a GH fragment with fat metabolism effects) can support body composition — preserving muscle mass during weight loss and improving fat metabolism — but are not weight loss treatments in the same sense as GLP-1 medications. They work best alongside dietary and GLP-1 interventions, particularly for patients focused on body composition rather than weight loss alone.
Who Qualifies for GLP-1 Weight Loss Injections?
Standard eligibility criteria for GLP-1 weight management prescriptions in Hong Kong:
BMI of 30 or above,or
BMI of 27 or above with one or more weight-related conditions (hypertension, dyslipidaemia, type 2 diabetes, insulin resistance, obstructive sleep apnoea)
Contraindications include personal or family history of medullary thyroid carcinoma or MEN2 syndrome, personal history of pancreatitis, pregnancy, and breastfeeding. A full medical review is required before any prescription is issued.
What a Proper Clinical Programme Looks Like
A responsible GLP-1 programme is not just a prescription service. At REVIV, the programme includes:
Initial doctor consultation — eligibility assessment, health history, goals, discussion of medication options
Baseline blood work — fasting glucose, HbA1c, liver and kidney function, lipids, thyroid
Prescription and medication — verified, regulated medication dispensed through licensed channels
Dose titration schedule — gradual dose increases to minimise side effects during the adjustment period
Ongoing monitoring — regular check-ins to manage side effects, adjust dosing, and track progress
Complementary support — IV nutritional therapy to compensate for reduced micronutrient intake; NAD+ for energy support; peptide protocols for muscle preservation where appropriate
Patients who attempt GLP-1 treatment without clinical oversight typically have more difficulty managing side effects and are more likely to discontinue. The programme structure exists because the medication works best when it's part of a monitored approach.
What Results Can You Realistically Expect?
Clinical trial averages are a useful reference, but individual results vary significantly. Factors that influence outcome include starting weight, adherence to dose titration, dietary changes made alongside the medication, activity levels, hormonal context, and genetic variation in GLP-1 receptor response.
In general:
Most patients experience noticeable appetite reduction within the first week
Meaningful weight loss (5–10% of body weight) is typical in the first 3–6 months
Peak weight loss in clinical trials occurs at 9–12 months
Weight typically returns when the medication is discontinued without durable lifestyle changes in place
GLP-1 medications are most effective as part of a programme that includes dietary guidance and physical activity — the medication reduces appetite and supports the metabolic environment, but lifestyle remains important for long-term maintenance.
Frequently Asked Questions
Are weight loss injections safe?
GLP-1 medications have strong safety profiles in appropriately screened patients. The most common side effects are gastrointestinal — nausea, constipation — and are typically manageable and transient. Serious side effects are rare but exist (pancreatitis, gallbladder disease). Clinical supervision throughout the programme is the appropriate safeguard.
How long do I need to take weight loss injections?
Most clinical programmes run 6–12 months or longer. Weight typically returns on discontinuation without sustainable lifestyle changes. Planning the programme duration and exit strategy with the treating doctor is part of the initial consultation.
Can I get weight loss injections online in Hong Kong?
Legitimate online pharmacy services in Hong Kong can dispense GLP-1 medications with a valid prescription. Unregulated online suppliers — particularly overseas — are not operating legally under Hong Kong law and cannot guarantee product authenticity or safety. A face-to-face consultation with a registered doctor is required for a legitimate prescription.
Do weight loss injections work without dieting?
GLP-1 medications produce significant weight loss even without formal dietary restriction, because they reduce appetite and caloric intake pharmacologically. However, the best outcomes are achieved when dietary quality and protein intake are maintained, and when the reduced appetite is used to establish healthier eating patterns rather than simply eating less of the same foods.
Start Your Weight Management Programme at REVIV Hong Kong
REVIV's GLP-1 weight management programme is doctor-led, with ongoing clinical oversight from consultation through to maintenance. If you're considering Ozempic or Mounjaro in Hong Kong, the first step is a consultation to assess your eligibility and discuss which approach best fits your profile and goals.
Location: 1st Floor, The Plaza, 21 D'Aguilar Street, Central, Hong Kong
Opening hours: Monday to Sunday, 10:00 AM – 7:00 PM
WhatsApp: +852 9867 9183
Sources
Wilding JPH et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). New England Journal of Medicine, 2021.
Jastreboff AM et al. Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1). New England Journal of Medicine, 2022.
Frías JP et al. Tirzepatide versus Semaglutide Once Weekly in Patients with Type 2 Diabetes (SURPASS-2). New England Journal of Medicine, 2021.
Drucker DJ.GLP-1 Physiology Informs the Pharmacotherapy of Obesity.New England Journal of Medicine, 2022.
Hong Kong Department of Health — Pharmacy and Poisons Ordinance: Prescription Drugs.
The material on this page is provided for informational purposes only and is not medical advice. Always consult your doctor before beginning any therapy programme. All therapies are subject to medical screening and doctor consultation to approve responsible treatment.
