Prescription weight loss medication

Prescription medication can be a useful addition to lifestyle measures for managing obesity.

A doctor discussing prescription weight loss medication with a patient

When will prescription medication be recommended for weight loss?

Prescription weight loss medication may be recommended if lifestyle strategies haven’t worked and your BMI remains over 30. They can also be recommended if you have obesity related complications and your BMI is between 27 and 30.1 2 3 4

They are also sometimes recommended after a person has been on a very low energy diet to prevent weight gain.5

How does prescription medication work?

Prescription medications usually reduce feelings of hunger. They also work by prolonging the feeling of fullness after eating.2 3 4

How well do prescription medicines work for weight loss?

Clinical studies of drug therapies have shown average weight loss of between 3% and 12% of your baseline bodyweight. This depends on your individual body type.

Studies show that your weight loss at 12-16 weeks predicts how much weight you’ll lose a year and beyond. If you haven’t lost at least 5% of your weight within three to four months or you need to lose more, your doctor will discuss additional options with you. 2 3 4

What happens if prescription medications don’t work?

Prescription weight loss medication doesn’t work for everyone. About 32-50% of people won’t lose 5% of their weight by this time.3 4

Although prescription medicines are promising for many in the short term, people rarely stay on them. Reasons include the cost, concerns about the side effects and a belief that it’s no longer necessary.2

If you’re one of the people who didn’t lose 5% of the starting weight in 3 months, or you are adversely impacted by the side effects, there are other options. Have a chat with your doctor about what other obesity treatment might be appropriate.

Weight loss surgery
1 Pilitsi E, et al. Pharmacotherapy of obesity: Available medications and drugs under investigation. Metab Clin Exp 2019; 92: 170–92.

2 Lee PC, Dixon J. Pharmacotherapy for obesity.Aust Fam Phys. 2017; 46(7): 472–7.

3 Saxenda Product Information. Available at December 2019.

4 Contrave Product Information. Available at Accessed December 2019.

5 ANZOS and ADS. 2020. The Australian Obesity Management Algorithm. Available at: https://static1.squaresp Accessed December 2021.