Does Ozempic make you constipated? Ozempic (semaglutide) is a GLP-1 receptor agonist licensed in the UK for type 2 diabetes management. While highly effective for glycaemic control, gastrointestinal side effects are commonly reported. Constipation is a recognised adverse reaction, affecting between 1 in 100 and 1 in 10 people according to the MHRA-approved Summary of Product Characteristics. This occurs because Ozempic slows gastric emptying and reduces gut motility—mechanisms that help regulate blood glucose but can delay bowel movements. Most cases are manageable with dietary adjustments, hydration, and lifestyle modifications, allowing patients to continue treatment successfully.

Does Ozempic Cause Constipation?

Ozempic (semaglutide) is a glucagon-like peptide-1 (GLP-1) receptor agonist licensed in the UK for the treatment of type 2 diabetes mellitus. Whilst it is highly effective in improving glycaemic control, gastrointestinal side effects are among the most commonly reported adverse reactions. Constipation is a recognised side effect of Ozempic, though it tends to be less frequently discussed than nausea or diarrhoea.

The mechanism by which Ozempic may cause constipation relates to its pharmacological action. GLP-1 receptor agonists slow gastric emptying and reduce gastrointestinal motility, which helps to regulate blood glucose levels by moderating the rate at which nutrients enter the bloodstream. This effect is most evident early in treatment. However, this slowing of gut transit can lead to delayed bowel movements and harder stools in some individuals. According to the Summary of Product Characteristics (SmPC), gastrointestinal effects are typically dose-dependent and may become more noticeable as the dose is escalated during the titration phase.

It is important to note that not everyone taking Ozempic will experience constipation. Individual responses vary considerably, and some patients may experience the opposite effect—diarrhoea or loose stools—particularly in the early weeks of treatment. The SmPC for Ozempic, as approved by the Medicines and Healthcare products Regulatory Agency (MHRA), lists constipation as a common adverse reaction (affecting between 1 in 100 and 1 in 10 people). Patients should be informed of this possibility when initiating therapy and reassured that, in most cases, symptoms are manageable with appropriate lifestyle and dietary adjustments.

How Common Is Constipation with Ozempic?

According to the Ozempic Summary of Product Characteristics (SmPC), constipation is classified as a 'common' adverse reaction, defined as affecting between 1 in 100 and 1 in 10 people treated with semaglutide for type 2 diabetes. By comparison, nausea is reported as 'very common' (affecting more than 1 in 10 people) and diarrhoea as 'common' in the clinical trials that formed the SUSTAIN programme.

The incidence of constipation may vary depending on several factors, including:

• Dose escalation schedule: Rapid increases in dose are associated with a higher frequency of gastrointestinal side effects, as noted in the European Medicines Agency's European Public Assessment Report (EPAR).

• Baseline bowel habits: Individuals with a history of slow transit constipation or irritable bowel syndrome may be more susceptible.

• Concurrent medications: Other drugs that slow gut motility—such as opioid analgesics, anticholinergics, or certain antidepressants—may compound the effect.

• Dietary changes: Reduced caloric intake may inadvertently decrease dietary fibre and fluid consumption, both of which are essential for regular bowel function.

It is also worth noting that constipation tends to be more prominent during the initial weeks of treatment and may improve as the body adjusts to the medication. However, some individuals experience persistent symptoms that require ongoing management. Healthcare professionals should routinely enquire about bowel habits during follow-up consultations, as patients may be reluctant to raise the issue spontaneously.

It should be noted that while Ozempic is licensed for type 2 diabetes, semaglutide is also available as Wegovy, which is specifically licensed for weight management in the UK at higher doses.

Managing Constipation While Taking Ozempic

Effective management of constipation in patients taking Ozempic begins with non-pharmacological interventions, which are often sufficient to restore normal bowel function. The following evidence-based strategies are recommended by NICE Clinical Knowledge Summaries (CKS) and NHS guidance:

• Increase dietary fibre intake: Aim for 25–30 grams of fibre daily from sources such as wholegrain cereals, fruits, vegetables, pulses, and nuts. Increase intake gradually to avoid bloating, and ensure adequate fluid intake. Soluble fibre (e.g., oats, linseeds) can be particularly helpful in softening stools.

• Maintain adequate hydration: The NHS recommends drinking 6–8 glasses of fluid daily, unless contraindicated by other medical conditions. Adequate fluid intake is essential for fibre to exert its beneficial effects on stool consistency.

• Engage in regular physical activity: Moderate exercise, such as brisk walking for 30 minutes most days, can stimulate bowel motility and improve transit time.

• Establish a regular bowel routine: Encourage patients to respond promptly to the urge to defecate and to allow sufficient time for bowel movements, ideally after meals when the gastrocolic reflex is most active.

If lifestyle measures are insufficient, pharmacological options may be considered in line with NICE CKS guidance on constipation. First-line laxatives include:

• Osmotic laxatives (e.g., macrogol): These draw water into the bowel, softening stools and promoting peristalsis. Macrogol is often preferred as first-line treatment for chronic constipation according to the British National Formulary (BNF).

• Bulk-forming laxatives (e.g., ispaghula husk, methylcellulose): These increase stool mass and are generally well tolerated, though they require adequate fluid intake and may worsen symptoms if fluid consumption is insufficient.

• Stimulant laxatives (e.g., senna, bisacodyl): These may be used short-term or longer-term with appropriate monitoring and review.

Patients experiencing persistent constipation should discuss with their prescriber whether slowing the dose titration or temporarily reducing the dose might help manage symptoms. They should be advised to avoid abrupt discontinuation of Ozempic solely due to constipation without first discussing management strategies with their GP or diabetes specialist nurse.

When to Seek Medical Advice About Bowel Changes

Whilst mild constipation is a recognised and manageable side effect of Ozempic, certain symptoms warrant prompt medical evaluation. Patients should be advised to contact their GP or NHS 111 if they experience:

• Severe or persistent constipation lasting more than one week despite lifestyle modifications and over-the-counter laxatives.

• Abdominal pain or distension that is severe, worsening, or accompanied by vomiting, which may indicate bowel obstruction or other serious complications.

• Rectal bleeding, particularly in those aged 50 and over, which requires investigation in line with NICE guideline NG12 on suspected cancer referral.

• Unexplained weight loss (beyond that expected from diabetes management) or loss of appetite.

• Change in bowel habit to looser or more frequent stools persisting for 6 weeks or more, particularly in those aged 60 and over, which may require assessment including faecal immunochemical testing (FIT) according to current NHS pathways.

It is also important to recognise that Ozempic has been associated with rare but serious gastrointestinal adverse effects, including pancreatitis. According to the SmPC, patients should stop taking semaglutide immediately and seek urgent medical attention if they develop severe, persistent abdominal pain radiating to the back, particularly if accompanied by nausea and vomiting, as these symptoms may indicate acute pancreatitis.

Healthcare professionals should conduct a thorough medication review if constipation becomes problematic, considering whether dose adjustment, temporary interruption, or alternative diabetes therapies may be appropriate. Shared decision-making is essential, balancing the metabolic benefits of Ozempic against the impact of gastrointestinal symptoms on quality of life. In most cases, with appropriate support and management, patients can continue treatment successfully whilst maintaining comfortable bowel function.

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