Semaglutide: An Overview of the GLP-1 Receptor Agonist for Diabetes Management

What is semaglutide? A GLP-1 medicine for type 2 diabetes, sold in Australia as Rybelsus tablets and Ozempic injections — and, for chronic weight management, as Wegovy. Rybelsus and Ozempic are registered for type 2 diabetes; Wegovy is the semaglutide product for weight management (healthdirect). All three are prescription-only. Of the three, this shop sells only Rybelsus.

Introduction to Semaglutide

Semaglutide belongs to a class of medicines known as GLP-1 receptor agonists. Medicines of this class increase the insulin you make after a meal, reduce the glucose your liver makes and help you feel full for longer after eating (healthdirect). It is an effective option for managing type 2 diabetes alongside diet and exercise, taken either as a tablet once a day (Rybelsus) or as an injection once a week (Ozempic).

How Semaglutide Works

Semaglutide works by activating GLP-1 receptors in the body:

  • More insulin after meals: it helps the pancreas release insulin when blood glucose is high.
  • Less glucose from the liver: it reduces the liver's glucose production.
  • Slower stomach emptying and fullness: food leaves the stomach more slowly and you feel full for longer.

In the Rybelsus tablet, semaglutide is combined with an absorption enhancer, salcaprozate sodium, so it can be absorbed from the stomach — which is why it must be taken on an empty stomach (Rybelsus PI).

Benefits of Semaglutide

  • Blood glucose control: it is registered to treat adults whose type 2 diabetes is not well enough controlled, on its own when metformin is not suitable or together with other diabetes medicines (healthdirect — Rybelsus).
  • Weight: in the Rybelsus trials in adults with type 2 diabetes, average weight fell by 2.3 kg on 7 mg and 3.7 kg on 14 mg over 26 weeks, against 1.4 kg on placebo (Rybelsus PI) — a trial result, not a promise, and not what Rybelsus is registered for.
  • A tablet or a weekly injection: the same medicine in two forms, with different doses — switching between them is your doctor's decision.

Semaglutide Commercial Names

Semaglutide is sold under three brand names in Australia:

  • Ozempic: a once-weekly injection pen for type 2 diabetes, on the PBS as an Authority Required item (PBS 14844G). We do not sell Ozempic.
  • Wegovy: semaglutide injection for chronic weight management (healthdirect). We do not sell Wegovy.
  • Rybelsus: Rybelsus is the brand name for the oral tablet form of Semaglutide — 3, 7 and 14 mg, once a day, registered for type 2 diabetes and not on the PBS. Its dosing, prices and the 30-minute rule are on the Rybelsus page.

Semaglutide can also be compared with other type 2 diabetes medicines:

  • Metformin: usually the first medicine for type 2 diabetes; it reduces the liver's glucose production and improves insulin sensitivity.
  • Sitagliptin (Januvia): a DPP-4 inhibitor tablet.
  • Liraglutide (Victoza): another GLP-1 medicine, injected once a day.

Semaglutide for Weight Loss

For weight loss, the semaglutide product registered in Australia is Wegovy, for chronic weight management; Rybelsus and Ozempic are registered for type 2 diabetes (healthdirect). Medicines prescribed for weight loss are not covered by Medicare (healthdirect). Using a diabetes medicine for weight loss is a decision for your doctor, not a reason to buy one.

Expected Weight Loss Results

For Rybelsus, the label reports weight as a trial result in people with type 2 diabetes: 2.3 kg (7 mg) and 3.7 kg (14 mg) on average over 26 weeks, against 1.4 kg on placebo (Rybelsus PI). Results in people without diabetes, at the higher doses used for weight management, belong to Wegovy's own label.

Dosage and Administration

  • Rybelsus (tablet): 3 mg once a day for the first month, then 7 mg; after at least a month on 7 mg the dose can go up to 14 mg, the maximum. Take it on an empty stomach with up to half a glass of water, swallowed whole, and wait at least 30 minutes before food, drink or other tablets (Rybelsus PI).
  • Ozempic (injection): once a week; the dose steps are set out in its own label.
  • Wegovy (injection): for weight management, with its own dose steps.

Your doctor sets the dose and decides when to step up.

Potential Side Effects

The common side effects are in the gut. With Rybelsus, nausea occurred in 15% of people, diarrhoea in 10% and vomiting in 7%; most were mild to moderate and short-lived, and 4% stopped treatment because of them (Rybelsus PI).

  • Dehydration: vomiting and diarrhoea can dehydrate you, which in rare cases can worsen kidney function — drink enough fluid.
  • Pancreatitis: severe, persistent pain in the stomach area can be acute pancreatitis; if it is suspected, semaglutide is stopped.
  • Hypoglycaemia: mainly a risk when it is taken with a sulfonylurea or insulin.

Precautions and Interactions

Tell your doctor about your medical history, especially pancreatitis. No dose adjustment is needed for kidney or liver impairment, but Rybelsus is not recommended in end-stage kidney disease (Rybelsus PI). Two medicines need monitoring when you start Rybelsus: levothyroxine and warfarin.

Warnings and Precautions

The Australian Rybelsus label has one contraindication: allergy to semaglutide or to anything else in the tablet (Rybelsus PI). It is not for type 1 diabetes, and it should not be used during pregnancy or breastfeeding. Semaglutide caused thyroid C-cell tumours in rats and mice, a known effect of GLP-1 medicines in rodents; the label considers the relevance for humans low, though it cannot be completely excluded — tell your doctor about any thyroid condition.

Semaglutide in Combination Therapies

Semaglutide can be used on its own when metformin is not suitable, or with other diabetes medicines:

  • With metformin: a common combination; metformin reduces the liver's glucose production and improves insulin sensitivity, semaglutide adds its GLP-1 effects.
  • With insulin or a sulfonylurea: your doctor may lower the insulin or sulfonylurea dose when semaglutide starts, to reduce the risk of low blood glucose.

Buying Semaglutide Online

Semaglutide is a prescription-only medicine in Australia. In June 2025 the TGA warned that counterfeit Rybelsus-labelled tablets with the batch number PS6LA8S had been stopped at the Australian border, and advised anyone holding that batch to stop using it (TGA, 25 June 2025). Check the batch number on every pack you receive.

Frequently Asked Questions (FAQs)

Is Semaglutide safe to take long-term?

It is used long-term in type 2 diabetes under a doctor's care, with the precautions above; the dose and the monitoring are your doctor's decision.

Can Semaglutide be combined with Metformin?

Yes — metformin is one of the medicines Rybelsus is registered to be used with.

What should I do if I experience gastrointestinal side effects while taking Semaglutide?

Nausea and diarrhoea are most common in the first months and usually settle. Drink enough fluid; see your doctor if they are severe or do not settle. Do not take Rybelsus with food to ease them — it must be taken fasting to be absorbed.

Does Semaglutide cause weight loss?

People with type 2 diabetes often lose some weight on it (see the trial figures above), but Rybelsus and Ozempic are registered for diabetes, not weight loss; the semaglutide product for weight management is Wegovy.

Can I take Semaglutide if I have a history of thyroid problems?

Tell your doctor: the label's thyroid note concerns tumours seen in rodents, whose relevance for humans it considers low but cannot exclude.