Wegovy Weight Loss Injection: Who It Is Approved For, How Much Weight to Expect, and Side Effects

You have been in Pattaya for a while, maybe a few months, maybe a couple of years, and you have decided you want a straight answer about Wegovy. Not a sales pitch. Not a wall of fine print. Just the facts: does it work, is it right for you, and can you start here?

This guide covers all of that. Who qualifies. What the dosing looks like week by week. How much weight you can realistically expect to lose. How to manage side effects when you are living in 35-degree heat. And what happens if you want to start treatment in Pattaya and continue it once you get home.

Who Qualifies for Wegovy and Who Should Avoid It

The approval criteria are specific. You qualify if your BMI is 30 or above. You also qualify if your BMI is 27 or above and you have at least one weight-related condition: high blood pressure, type 2 diabetes, or high cholesterol, for example. These are clinical thresholds, not soft guidelines.

Wegovy also has solid evidence for cardiovascular risk reduction. The SELECT trial, published in 2023, found that semaglutide at this dose reduced the risk of serious cardiovascular events in people with existing heart disease and overweight or obesity who did not have diabetes. In 2024, the US FDA added this use to the Wegovy label.

Who should not take it? Anyone with a personal or family history of medullary thyroid carcinoma, a type of thyroid cancer, should avoid Wegovy. The same applies if you have MEN2, a rare hereditary condition affecting the endocrine glands. Wegovy is also not appropriate during pregnancy. If you have had pancreatitis before, your doctor needs to know before you start, as Wegovy has not been studied in people with past pancreatitis. Wegovy is also not recommended for people with severe gastroparesis, a condition where the stomach empties too slowly, since Wegovy slows stomach emptying.

What the Wegovy Dosing Schedule Actually Looks Like

Wegovy is injected once a week, under the skin, using a pre-filled pen. The dose starts low and increases gradually over several months. This step-up approach is designed to reduce stomach side effects.

Some people notice appetite changes early, while others notice more as the dose goes up. Stomach side effects such as nausea are more common during the dose increase phase.

Inject into the abdomen, upper arm, or thigh. Rotate the site each week to avoid tissue irritation.

How Much Weight You Can Realistically Expect to Lose on Wegovy

The STEP 1 trial is the most reliable data we have. People taking Wegovy at 2.4mg lost an average of around 15% of their starting body weight over 68 weeks, combined with a reduced-calorie diet and increased physical activity. A 2025 trial called STEP UP, testing a higher 7.2mg semaglutide dose, reported approximately 21% average body weight reduction over 72 weeks. That higher dose was approved in the EU and the US in early 2026 for some adults, but it may not be available in every country yet.

These are averages. Individual results vary. What the data consistently shows is that Wegovy produces meaningful weight loss that lasts for as long as it is taken properly and combined with lifestyle changes.

Weight loss typically slows and then levels off over time. That plateau is normal and does not mean the medication has stopped working. Adjusting your diet and activity at that point can help move things forward again.

Managing Side Effects in Pattaya’s Heat

The most common side effects are nausea, vomiting, constipation, diarrhoea, and abdominal discomfort. They tend to be worst during dose increases and improve between steps. For most people they are mild to moderate and ease over time.

Vomiting and diarrhoea can cause dehydration, which can harm the kidneys, and Pattaya’s heat adds to that risk. If you are already queasy and sweating in the midday sun, staying hydrated takes active effort. Small sips throughout the day work better than large amounts at once when your stomach is unsettled.

Eating smaller portions slowly, and avoiding very greasy or spicy food during the early weeks, makes a real difference. Thai food is one of the great pleasures of living here, but a full green curry on week two of dose escalation is a setup for a rough evening.

If you develop severe or persistent abdominal pain, stop the injection and get seen. Pancreatitis is uncommon but presents exactly this way and needs urgent assessment. Gallbladder problems are also a known risk with rapid weight loss. Sudden right-sided pain after eating warrants a visit. Also get help quickly for swelling of the face or throat, trouble breathing, or a lump in your neck, trouble swallowing, or a hoarse voice.

Doctor Pattaya is open 24 hours a day. If a side effect concern hits at 2am, you do not need to wait until morning.

Starting Your Wegovy Consultation in Pattaya

Whether you have lived here for years or you are passing through for a few weeks, the process is straightforward. Before you start, a doctor needs to review your medical history, current medications, and any contraindications.

If Wegovy is appropriate for you, your doctor should go through the dosing schedule, what to expect in the first weeks, and how to inject correctly. Full details about the GLP-1 weight loss programme, including what to expect at your first appointment, are on our Wegovy weight loss injection guide.

If you start a course here and continue at home, ask for written records of your starting weight, the dose you received, and the schedule going forward. This helps your GP or specialist at home continue your care.

How to Store Your Wegovy Pen in Thailand’s Climate

This matters more here than almost anywhere else. Wegovy pens must be kept refrigerated between 2°C and 8°C before first use. Once you start using a multi-dose FlexTouch pen, it can be kept below 30°C for up to 6 weeks, and it must not be frozen. Single-dose pens can be kept out of the fridge below 30°C for up to 28 days.

Pattaya’s ambient temperature regularly sits above 30°C, especially outdoors and in vehicles. Do not leave your pen in a beach bag in the sun, in a car, or in a hotel room without air conditioning running. Too much heat can damage the medication.

When travelling, carry the pen in an insulated medical pouch with an ice pack if needed. This applies whether you are spending a full day at Jomtien Beach or heading up to Bangkok for the weekend. If you are unsure whether your pen has been heat-damaged, come in before injecting. Do not use a pen that may have been compromised.

How Long You Need to Take Wegovy and What Happens If You Stop

Wegovy is a long-term treatment. The weight loss it produces depends on the medication continuing to work. When you stop, those effects stop.

A 2022 withdrawal study published in Diabetes, Obesity and Metabolism found that participants regained, on average, about two thirds of the weight they had lost within one year of stopping semaglutide. The body tends to return toward its previous set point once the drug is no longer active. That is not a failure of willpower. It reflects the biology of obesity.

This is especially relevant if you are starting Wegovy in Pattaya before returning home. The plan for continuity matters as much as the first injection. Make sure you have a prescriber ready at home before you start here. If you need a doctor visit in Pratumnak or anywhere across South Pattaya to discuss that plan, we can arrange it around you.