Liraglutide is a Therapeutic Goods Administration (TGA)-approved drug to assist with weight loss.
The drug is sold under the brand name Saxenda for weight loss (and is also sold in a lower dose as Victoza for the treatment of type-2 diabetes).
But how effective is it? And is it worth the high monthly cost and potential side effects?
Saxenda (Liraglutide) is a self-injectable medication used for weight loss.
How does Saxenda work?
Saxenda is a self-injectable prescription medication that's similar to the human hormone (GLP-1), which regulates hunger. It works by helping to suppress your appetite, which can lead to you consuming fewer calories.
It can be prescribed to people with a body mass index (BMI) of 30 or more, or people with a BMI of 27–29 with weight-related conditions, such as prediabetes, type-2 diabetes, high blood pressure, high cholesterol, or sleep apnoea.
How much does Saxenda cost?
Saxenda costs about $400 a month by private prescription. It's not subsidised by the Pharmaceutical Benefits Scheme (PBS).
How effective is Saxenda?
In a large 56-week study sponsored by the manufacturer, three in five people (63.2%) taking the drug – in combination with a reduced-energy diet and increased exercise – lost at least five per cent of their body weight, and one in three (33.1%) lost more than 10%.
The patients had an average starting weight of about 106kg, and lost an average of 8.4kg over the time. There were other health improvements, including blood glucose, blood pressure and cholesterol levels.
A group of patients who received only lifestyle-modification advice (ie, without taking Saxenda) lost 2.8kg on average.
Should I take it?
Talk to your doctor about whether or not it's suitable for you.
However, given its cost of more than $5000 a year for an average weight loss of about 5–6kg more than lifestyle counselling alone, you also need to weigh up the cost versus benefits.
For more information, NPS MedicineWise has a detailed Saxenda consumer information leaflet.
What are the side effects?
The main side effects of taking Saxenda are:
- nausea
- vomiting
- diarrhoea
- constipation.
Less common, but more serious, side effects include:
- hypoglycaemia (especially for people taking diabetes medication)
- pancreatitis
- gallbladder disease
- thyroid tumours
- renal (kidney) impairment
- depression
- suicidal thoughts.
Talk to your doctor before taking any weight-loss medicines to make sure they're right for you.
What other medicines help with weight loss?
Your main options for weight loss medications in Australia are Xenical (orlistat), Duromine (phentermine) and Contrave (naltrexone hydrochloride and bupropion hydrochloride).
Xenical (orlistat)
Works in your stomach and intestine by preventing your body from absorbing some of the fat you eat, helping you to lose weight.
Some dietary modification may be needed – if you eat too much fat, you may suffer side effects such as oily bowel movements and seepage, flatulence, faecal incontinence, diarrhoea and abdominal pain.
Xenical is available over the counter for about $120 a month (if taken three times a day).
Duromine (phentermine)
This is an amphetamine-like drug that helps with weight loss by suppressing appetite.
Side effects
Phentermine side effects include tachycardia (rapid heart beat), palpitations, insomnia, anxiety and elevated blood pressure. It's not on the PBS, and costs about $100–140 per month.
Qsymia (phentermine and topiramate)
In the US, phentermine is also available in combination with anti-epilepsy drug topiramate (Topamax and generic), which also works as an appetite suppressant.
The weight loss in the combination drug, known as Qsymia, is greater than with phentermine alone.
Side effects
Side effects are relatively rare, but some are potentially serious, and include headaches, palpitations, insomnia, paresthesia (tingling, numbness, pins and needles), depression and suicidal thoughts. An Australian study of 103 people had 61 drop out, including 41 because they couldn't tolerate the side effects.
Qsymia was rejected in Europe due to safety concerns
Qsymia was rejected in Europe due to safety concerns – in particular the cardiovascular and mental-health effects.
The combination hasn't been approved by the TGA for weight loss in Australia, although the individual drugs may be prescribed 'off label' by a doctor (ie, for a use that isn't included in the approved product information document).
Contrave (naltrexone hydrochloride and bupropion hydrochloride)
Contrave is a relative newcomer on the market, having been approved for weight loss by the TGA in 2019.
It's a combination of two medications, one an antidepressant and the other used to treat addiction. These work together in the brain to suppress hunger signals.
Side effects
Some common side effects include nausea and vomiting, constipation, diarrhoea and dizziness. More serious side effects such as seizures, liver damage, high blood pressure, hypoglycaemia, manic episodes and visual problems may also occur.
It is not on the PBS and is available with a prescription for about $240 per month.
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