Treating obesity is always a multidisciplinary process. It requires a combination of healthy eating and regular physical activity.
In some cases, weight loss medications can support these efforts. While they’re not a standalone solution, certain treatments may help manage appetite, improve metabolic health, or enhance the results of lifestyle changes.
So, what medications are available? Let’s take a closer look.
Newer Generation Medications
These treatments are at the forefront of obesity care and show promising results, especially when combined with lifestyle changes:
GLP-1 Analogues (e.g. Saxenda, Wegovy)
These medications mimic a natural hormone that helps regulate appetite and slow digestion. They are administered as daily or weekly injections and must be prescribed and monitored by your doctor. Research indicates that they can support weight loss of 5-15% when used in conjunction with lifestyle changes. Pharmac has recently approved Wegovy, which will be available in New Zealand from July 2025.
GLP-1/GIP Combination Treatments (e.g. Mounjaro)
These newer medications combine two gut hormones, GLP-1 and GIP, to reduce appetite and improve blood sugar control. Early research suggests that this combination can support even greater weight loss, with some individuals losing up to 20% of their body weight. Although approved overseas for both diabetes and weight loss, these treatments are not currently available in New Zealand.
Bupropion/Naltrexone (e.g. Contrave)
This combination of medications includes Bupropion, an antidepressant that also supports smoking cessation, and Naltrexone, which helps reduce side effects like nausea. Together, they work on the brain’s hunger and reward pathways to reduce appetite and manage cravings. Contrave is taken as a daily tablet and may support weight loss when used in conjunction with a healthy diet and regular physical activity. It is available in New Zealand with a prescription.
Who Might Be Eligible?
Bariatric surgery is typically considered for people who meet certain criteria:
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BMI over 40
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BMI over 35 with complications such as type 2 diabetes or heart disease
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BMI over 30 with poorly controlled type 2 diabetes
People with a BMI over 50 may be encouraged to lose some weight beforehand, often with the help of GLP-1 medications and lifestyle changes, to reduce surgical risks and improve outcomes.
Types of Bariatric Surgery and Procedures
There are both non-surgical (endobariatric) and surgical options available. The most suitable approach depends on your individual health needs and medical history.
Non-Surgical (Endobariatric) Options
These procedures are performed via endoscopy and do not require traditional surgery.
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Intragastric balloon: A balloon is placed in the stomach to reduce space and increase the feeling of fullness.
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Endoscopic sleeve gastroplasty: The stomach is stitched internally to reduce its volume. This is a newer technique that is currently offered privately.
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Gastric bypass revision: For those who have had previous surgery, this endoscopic procedure tightens the original bypass to improve results.
Surgical Options
These procedures involve physical changes to the stomach or digestive tract.
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Gastric banding: A band is placed around the upper part of the stomach to reduce food intake and increase fullness. This procedure was once common but is now rarely used due to better long-term results from other surgical options.
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Gastric sleeve (sleeve gastrectomy): The size of the stomach is reduced by removing part of it and reshaping it into a narrow tube. This helps you feel full more quickly and stay full for longer, which reduces how much you eat. It is a highly effective method for weight loss and has also been shown to improve symptoms of type 2 diabetes. A common complication is reflux. In some cases, the stomach may stretch again over time, requiring another procedure to restore the original effect.
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Gastric bypass: This surgery changes how your stomach and small intestine process food. A small pouch is created at the top of the stomach to reduce how much food you can eat at one time. The pouch is then connected to the lower part of the small intestine, which reduces how much food and nutrients are absorbed. There are two main types of gastric bypass:
One anastomosis gastric bypass (sometimes called a mini bypass): A small stomach pouch is connected directly to the small intestine, bypassing a section of the stomach and upper intestine. Despite the name, this is still a major procedure with significant effects.
Roux-en-Y gastric bypass: This procedure creates a small stomach pouch and connects it to the small intestine in two places. One connection joins the pouch to the small intestine. The second connects two parts of the intestine further along, which helps reroute the digestive path.Both types of bypass are effective for weight loss and for improving or even reversing conditions like type 2 diabetes. As with all bariatric surgeries, follow-up care and ongoing support are crucial for achieving long-term success.
What Happens After Surgery?
Ongoing support is essential for long-term success. Most patients will:
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Work closely with a dietitian or nutritionist
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Take daily multivitamins and supplements
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Have regular follow-ups to monitor nutrition, weight, and health
Final Thoughts
Bariatric surgery is one option in a comprehensive approach to treating obesity. It’s not a quick fix, but when paired with lifestyle changes and clinical support, it can offer life-changing benefits.
If you’re considering weight loss options, I run a dedicated weight loss clinic every Wednesday at Devonport Health Centre. Together, we can create a plan that suits your lifestyle and goals. Please speak to reception for more details.