Ozempic (semaglutide) is a once-weekly injectable medication licensed in the UK for treating type 2 diabetes in adults. As a glucagon-like peptide-1 (GLP-1) receptor agonist, it works by stimulating insulin release in a glucose-dependent manner, suppressing glucagon, and slowing gastric emptying. A common question amongst patients and healthcare professionals concerns whether Ozempic helps hypoglycaemia or increases its risk. Understanding this relationship is crucial for safe prescribing and effective diabetes management. This article examines the evidence surrounding Ozempic and hypoglycaemia, clarifying its mechanism, risk profile, and appropriate clinical use in accordance with UK guidance from NICE, the MHRA, and NHS recommendations.

What Is Ozempic and How Does It Work?

Ozempic (semaglutide) is a prescription medication licensed in the UK for the treatment of type 2 diabetes mellitus in adults. It belongs to a class of medicines called glucagon-like peptide-1 (GLP-1) receptor agonists, which work by mimicking the action of a naturally occurring hormone that helps regulate blood glucose levels.

The medication is administered as a once-weekly subcutaneous injection, typically into the abdomen, thigh, or upper arm. Ozempic is available in pre-filled pens containing different dosage strengths, with a standard UK titration schedule starting at 0.25 mg weekly for 4 weeks, then increasing to 0.5 mg weekly, with further increases if needed. The Medicines and Healthcare products Regulatory Agency (MHRA) has approved Ozempic for use alongside diet and exercise to improve glycaemic control in adults with type 2 diabetes. It is not indicated for type 1 diabetes or for the treatment of diabetic ketoacidosis.

Mechanism of action: Ozempic works through several complementary pathways. Firstly, it stimulates insulin secretion from pancreatic beta cells, but crucially, this effect is glucose-dependent—meaning insulin is only released when blood glucose levels are elevated. Secondly, it suppresses the release of glucagon, a hormone that raises blood sugar levels, particularly after meals. Thirdly, semaglutide slows gastric emptying, which moderates the rate at which glucose enters the bloodstream following food intake. Additionally, it acts on appetite centres in the brain, promoting satiety and often leading to weight reduction.

This glucose-dependent mechanism is particularly important from a safety perspective, as it distinguishes GLP-1 receptor agonists from some other diabetes medications. According to NICE guidance (NG28), Ozempic may be considered in specific circumstances, such as when a person has a BMI ≥35 kg/m² (or lower in certain ethnic groups), when weight loss would benefit obesity-related comorbidities, or when other glucose-lowering therapies are not effective, tolerated or contraindicated.

Understanding Hypoglycemia Risk with Ozempic

Hypoglycaemia (low blood sugar) occurs when blood glucose levels fall below 4.0 mmol/L, potentially causing symptoms such as trembling, sweating, confusion, palpitations, and in severe cases, loss of consciousness. Understanding the hypoglycaemia risk profile of any diabetes medication is essential for both patients and healthcare professionals.

When used as monotherapy (on its own) or in combination with metformin, Ozempic carries a very low risk of hypoglycaemia. This favourable safety profile stems from its glucose-dependent mechanism of action—insulin secretion is only stimulated when blood glucose levels are elevated, and the effect diminishes as glucose levels normalise. According to the Ozempic Summary of Product Characteristics (SmPC), the incidence of hypoglycaemia with semaglutide monotherapy is similar to placebo in clinical trials.

However, the risk profile changes when Ozempic is used in combination with certain other diabetes medications. The highest risk occurs when Ozempic is combined with:

• Sulphonylureas (such as gliclazide, glimepiride, or glipizide)

• Insulin therapy

These medications work through glucose-independent mechanisms, meaning they stimulate insulin release or provide exogenous insulin regardless of blood glucose levels. When combined with Ozempic, the cumulative glucose-lowering effect can increase hypoglycaemia risk. The SmPC for Ozempic notes that dose reduction of sulphonylureas or insulin may be necessary when initiating semaglutide treatment.

Patient awareness is crucial. Those taking Ozempic alongside sulphonylureas or insulin should be educated about hypoglycaemia symptoms, carry fast-acting carbohydrates (such as glucose tablets or sugary drinks), and understand when to seek medical advice. Regular blood glucose monitoring is recommended, particularly during treatment initiation or dose adjustments. Patients should also be aware of DVLA guidance regarding diabetes and driving, especially if taking medications that increase hypoglycaemia risk.

Managing Blood Sugar Levels While Taking Ozempic

Effective blood glucose management whilst taking Ozempic requires a comprehensive, individualised approach that extends beyond medication alone. Healthcare professionals typically recommend a combination of lifestyle modifications, monitoring strategies, and medication optimisation.

Dietary considerations play a fundamental role. Patients should aim for a balanced diet rich in fibre, with controlled portions of complex carbohydrates distributed throughout the day. Given that Ozempic slows gastric emptying and reduces appetite, some individuals may experience early satiety or gastrointestinal symptoms. Eating smaller, more frequent meals and avoiding high-fat foods can help manage these effects whilst maintaining stable blood glucose levels. The NHS Eatwell Guide provides practical advice on balanced nutrition for people with diabetes.

Blood glucose monitoring requirements vary depending on individual circumstances and concurrent medications. Whilst routine self-monitoring may not be necessary for all patients taking Ozempic, it becomes important when:

• Ozempic is combined with sulphonylureas or insulin

• Symptoms suggestive of hypoglycaemia or hyperglycaemia occur

• During illness or periods of altered eating patterns

• When adjusting medication doses

Physical activity contributes significantly to glycaemic control. Regular exercise improves insulin sensitivity and helps maintain healthy body weight. Patients should be advised that exercise can lower blood glucose levels, and those on combination therapy with hypoglycaemia-inducing medications may need to adjust timing of meals or medication around physical activity.

Medication review should occur regularly with healthcare professionals. NICE recommends monitoring HbA1c levels every 3–6 months to assess overall glycaemic control. Target HbA1c levels are typically 48 mmol/mol for most adults with type 2 diabetes at low risk of hypoglycaemia, or 53 mmol/mol for those on medications that can cause hypoglycaemia (such as sulphonylureas or insulin), with individualisation based on personal circumstances. If targets are not achieved, treatment intensification may be considered. Conversely, if hypoglycaemia occurs, dose reduction of sulphonylureas or insulin—rather than Ozempic—is usually the appropriate intervention.

Patients should be encouraged to attend regular diabetes reviews, maintain open communication with their healthcare team, and report any concerns about blood glucose control promptly. Any suspected side effects can be reported via the MHRA Yellow Card scheme.

Does Ozempic Help Hypoglycemia or Cause It?

This question requires careful clarification, as there is often confusion about Ozempic's relationship with hypoglycaemia. Ozempic does not help treat hypoglycaemia—it is not indicated for, nor effective in, raising low blood sugar levels. Rather, it is a glucose-lowering medication designed to reduce elevated blood glucose in people with type 2 diabetes.

The more pertinent question is whether Ozempic causes hypoglycaemia. The evidence-based answer is nuanced:

As monotherapy or with metformin: Ozempic has a very low intrinsic risk of causing hypoglycaemia. Its glucose-dependent mechanism means it does not drive blood glucose below normal physiological levels when used alone. According to the Ozempic SmPC, hypoglycaemia rates are similar to placebo in these settings.

In combination with sulphonylureas or insulin: The risk of hypoglycaemia increases. This is not because Ozempic itself directly causes hypoglycaemia, but rather because the combined glucose-lowering effects of multiple medications can result in blood glucose falling too low. In clinical trials, when semaglutide was added to existing sulphonylurea or insulin therapy, hypoglycaemia rates increased compared to monotherapy.

Important safety considerations:

• Patients starting Ozempic whilst taking sulphonylureas or insulin should have these medications reviewed and potentially dose-reduced

• GLP-1 receptor agonists rarely cause hypoglycaemia when not used with insulin or sulphonylureas

• Hypoglycaemia symptoms should never be ignored—patients should consume 15–20g of fast-acting carbohydrate and recheck glucose after 15 minutes

• If someone is unconscious or unable to swallow safely, call 999 immediately, place them in the recovery position, and use glucagon if available and you are trained to do so

• Recurrent hypoglycaemia warrants urgent medical review

When to contact your GP or diabetes team:

• Experiencing hypoglycaemia (blood glucose <4.0 mmol/L) more than once weekly

• Severe hypoglycaemia requiring assistance from others

• Uncertainty about medication management

• Planning significant lifestyle changes that may affect blood glucose

In summary, Ozempic is a glucose-lowering medication with a low intrinsic hypoglycaemia risk when used appropriately, but it does not treat or prevent hypoglycaemia. Proper patient selection, medication review, and ongoing monitoring are essential for safe and effective use.

Frequently Asked Questions