Ozempic contains semaglutide, a once-weekly injection registered in South Africa to treat type 2 diabetes. It lowers blood sugar and reduces cardiovascular risk, and it also causes substantial weight loss. It is a prescription medicine, and demand for weight loss has driven shortages and counterfeits.
What is Ozempic?
Ozempic contains semaglutide, supplied as a pre-filled pen for once-weekly injection under the skin. It is a Schedule 4 prescription medicine.
Semaglutide is a GLP-1 receptor agonist. GLP-1 is a hormone your gut releases when you eat. It does several things at once, and semaglutide mimics all of them for a full week per injection:
- Prompts the pancreas to release insulin — but only when blood sugar is raised, which is why it rarely causes low blood sugar on its own.
- Reduces glucagon, the hormone that pushes the liver to release stored sugar.
- Slows stomach emptying, so food leaves the stomach more gradually.
- Acts on appetite centres in the brain, reducing hunger and food-seeking.
Those last two produce the weight loss. People eat less because they feel full sooner and stay full longer, and because the constant background pull toward food quietens.
In South Africa, Ozempic is registered for type 2 diabetes. A higher-dose semaglutide product, Wegovy, is the version developed specifically for weight management. Prescribing Ozempic for weight loss alone is off-label, and it is common — which has consequences covered below.
What is Ozempic commonly used for?
- Type 2 diabetes, to improve blood sugar control alongside diet and exercise.
- Reducing cardiovascular risk in people with type 2 diabetes and established heart disease — semaglutide reduces heart attacks, strokes and cardiovascular death, which is a genuinely important finding.
- Weight management, where prescribed for that purpose.
It is not for type 1 diabetes, and it does not replace insulin.
On using it for weight loss
Semaglutide works for weight loss — that is not in question. Several things about it are worth knowing before starting:
Weight returns when you stop. Trials consistently show most of the lost weight comes back within a year or two of stopping. It is a treatment for an ongoing condition, not a course you complete. That has cost and planning implications people are often not told.
It works alongside diet and activity, not instead of them. Muscle is lost along with fat, and resistance exercise and adequate protein reduce that.
Demand has caused shortages. People with type 2 diabetes who depend on it have struggled to fill prescriptions because of weight-loss demand — a real and documented problem in South Africa.
Counterfeit pens are circulating. Falsified semaglutide has been found internationally and in South Africa, some containing insulin instead, which has caused hospitalisations from severe hypoglycaemia. Buy only from a licensed pharmacy with a prescription. Never buy an injectable medicine online, through social media, or from a gym or salon.
How Ozempic fits into this medicine category
| Group | Examples | Role |
|---|---|---|
| GLP-1 receptor agonists | Semaglutide (Ozempic, Wegovy), liraglutide, dulaglutide | Blood sugar, weight, cardiovascular risk |
| Biguanides | Metformin | Usual first-line treatment in type 2 diabetes |
| SGLT2 inhibitors | Empagliflozin, dapagliflozin | Blood sugar, heart and kidney protection |
| Sulfonylureas | Gliclazide, glimepiride | Lower blood sugar; risk of hypoglycaemia |
| Insulin | Various | Type 1 diabetes; advanced type 2 |
Metformin remains the usual starting point in type 2 diabetes; semaglutide is typically added where control is inadequate or where weight and cardiovascular risk matter. See the endocrine and diabetes medicines hub.
What to check before using Ozempic
Inject it once weekly, on the same day each week, into the abdomen, thigh or upper arm, rotating the site. It can be given at any time of day, with or without food.
Expect the dose to be increased slowly. Starting low and building up over weeks is what makes the nausea manageable. Rushing it is the commonest reason people abandon treatment.
Learn the injection technique properly from a pharmacist or nurse, and dispose of needles in a sharps container.
Tell your prescriber or pharmacist if you:
- Have a personal or family history of medullary thyroid carcinoma, or multiple endocrine neoplasia type 2 — semaglutide is not used in either.
- Have had pancreatitis.
- Have gallstones, or have had them.
- Have diabetic retinopathy. Rapid improvement in blood sugar can temporarily worsen it, so eye monitoring matters.
- Have kidney disease — dehydration from vomiting can worsen it.
- Have severe gut problems, including gastroparesis.
- Are pregnant, planning pregnancy or breastfeeding. It is stopped well before a planned pregnancy.
- Take insulin or a sulfonylurea — those amounts usually need reducing, or blood sugar can drop dangerously.
- Are due surgery or a procedure under sedation. Tell the anaesthetist you take it; delayed stomach emptying raises the risk of aspiration, and fasting instructions may differ.
Follow the dispensing label exactly. This page does not set doses.
Possible cautions and when to ask a pharmacist or doctor
Nausea is very common, particularly when starting or increasing the dose. Vomiting, diarrhoea, constipation and reflux also occur. Smaller meals, eating slowly, stopping when full, and avoiding fatty or very large meals all help considerably, and it usually eases over weeks.
Pancreatitis is rare but serious. Stop the medicine and seek urgent care for severe, persistent abdominal pain, particularly pain radiating to the back, with or without vomiting.
Gallstones are more common with rapid weight loss. Report right-sided upper abdominal pain, particularly after fatty meals.
Dehydration. Persistent vomiting or diarrhoea can affect kidney function — keep fluids up and seek advice if it continues.
Low blood sugar is uncommon with semaglutide alone but likely if you also take insulin or a sulfonylurea. Know the symptoms — shakiness, sweating, confusion, hunger — and how to treat them.
Do not share a pen, even with a new needle. This transmits blood-borne infection.
Do not stop abruptly if you have diabetes without a plan for blood sugar control.
Seek urgent medical attention for severe abdominal pain radiating to the back; persistent vomiting; signs of dehydration; sudden changes in vision; severe low blood sugar; a rapid heartbeat; or swelling of the face, lips or tongue with difficulty breathing.
Related medicine guides
Frequently asked questions
What is Ozempic used for? It is registered in South Africa to treat type 2 diabetes, and it also reduces cardiovascular risk in people with diabetes and heart disease. It causes substantial weight loss, and is widely prescribed off-label for that.
Is it a weight-loss injection? It causes weight loss, but in South Africa Ozempic is registered for type 2 diabetes. Wegovy is the higher-dose semaglutide developed for weight management.
Will the weight come back if I stop? Usually, yes. Trials show most lost weight returns within a year or two of stopping. It treats an ongoing condition rather than being a course you finish.
Why does it make me nauseous? It slows stomach emptying. Nausea is commonest when starting or increasing the dose, and usually eases. Smaller meals and eating slowly help.
Can I buy it online? No. Counterfeit semaglutide pens are circulating, some containing insulin, and have caused hospitalisations. Buy only from a licensed pharmacy with a prescription.
Do I need to tell my anaesthetist? Yes. Delayed stomach emptying raises the risk during sedation, and fasting instructions may need to change.