Wegovy (semaglutide 2.4 mg) is a GLP-1 receptor agonist licensed in the UK for chronic weight management in adults with obesity or overweight with weight-related comorbidities. Whilst haemorrhoids are not listed as a direct adverse effect in the Summary of Product Characteristics, Wegovy's gastrointestinal side effects—particularly constipation, affecting approximately 24% of users—may indirectly increase the risk of developing or worsening haemorrhoids. Understanding this potential link and implementing effective bowel management strategies can help minimise discomfort whilst maintaining treatment efficacy. This article examines the relationship between Wegovy and haemorrhoid development, offering practical guidance for patients and clinicians.
Quick Answer: Wegovy does not directly cause haemorrhoids, but its gastrointestinal side effects—particularly constipation affecting approximately 24% of users—may indirectly increase the risk of developing or worsening haemorrhoids through straining during bowel movements.
Wegovy (semaglutide 2.4 mg) is a glucagon-like peptide-1 (GLP-1) receptor agonist licensed by the MHRA for chronic weight management in adults with obesity or overweight with weight-related comorbidities. It works by mimicking the naturally occurring hormone GLP-1, which regulates appetite and food intake by acting on receptors in the brain, pancreas, and gastrointestinal tract.
The medication slows gastric emptying, enhances feelings of satiety, and reduces hunger signals, leading to decreased caloric intake and subsequent weight loss. Wegovy is administered once weekly via subcutaneous injection and is intended for use alongside a reduced-calorie diet and increased physical activity.
In the UK, Wegovy is available through specialist weight management services and prescribed for a maximum duration as specified in NICE Technology Appraisal 875.
Common side effects predominantly affect the gastrointestinal system, reflecting the drug's mechanism of action. According to the Summary of Product Characteristics (SmPC), the most frequently reported adverse effects include:
Nausea (affecting up to 44% of patients initially)
Diarrhoea (affecting approximately 30% of users)
Vomiting (reported in around 24% of patients)
Constipation (occurring in approximately 24% of individuals)
Abdominal pain and dyspepsia
These gastrointestinal symptoms typically emerge during dose escalation and often diminish over time as the body adapts to the medication. The gradual dose titration schedule outlined in the SmPC aims to minimise these effects. Other reported side effects include injection site reactions, fatigue, and dizziness. Serious but rare adverse events include pancreatitis, gallbladder disease, and hypoglycaemia (particularly in patients taking concomitant diabetes medications).
Maintaining adequate hydration is essential during Wegovy treatment, as gastrointestinal side effects may increase the risk of dehydration and potentially affect kidney function.
The gastrointestinal side effects associated with Wegovy arise directly from its pharmacological action on the digestive system. GLP-1 receptors are abundantly expressed throughout the gastrointestinal tract, and semaglutide's activation of these receptors produces several physiological changes that can affect bowel function.
Primarily, Wegovy delays gastric emptying, meaning food remains in the stomach for longer periods before moving into the small intestine. This mechanism contributes to prolonged satiety but can also lead to feelings of fullness, bloating, nausea, and in some cases, vomiting. The altered motility affects the entire digestive tract, potentially influencing bowel habits in various ways.
Constipation is a particularly relevant side effect when considering haemorrhoid development. Approximately one in four patients taking Wegovy experience constipation, which occurs due to slowed intestinal transit time. Conversely, diarrhoea affects a similar proportion of users, possibly due to altered fluid secretion and absorption in the intestines.
These opposing effects on bowel habits—constipation in some individuals and diarrhoea in others—reflect individual variation in how the gastrointestinal system responds to GLP-1 receptor activation. Both conditions can theoretically contribute to anorectal symptoms, including haemorrhoid development or exacerbation.
The intensity of gastrointestinal symptoms typically correlates with dose escalation. Clinical trials, including the STEP programme (Semaglutide Treatment Effect in People with obesity), demonstrate that these effects are most pronounced during the initial weeks of treatment and when increasing to higher doses. Most patients experience gradual improvement as treatment continues, though some individuals may have persistent symptoms requiring management strategies or, occasionally, treatment discontinuation.
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Start HereHaemorrhoids are not listed as an adverse reaction in the Wegovy Summary of Product Characteristics (SmPC), and they did not emerge as a significant safety signal during the STEP (Semaglutide Treatment Effect in People with obesity) clinical trial programme.
However, an indirect relationship may exist through Wegovy's gastrointestinal effects. Haemorrhoids develop when increased pressure is applied to the venous cushions in the anal canal, causing them to swell and become symptomatic. The primary risk factors include:
Chronic constipation and straining during bowel movements
Prolonged sitting on the toilet
Diarrhoea (less commonly, but repeated episodes can contribute)
Increased intra-abdominal pressure
Given that Wegovy causes constipation in approximately 24% of users, patients who develop this side effect may experience harder stools and increased straining during defecation. This straining elevates pressure in the haemorrhoidal venous plexus, potentially triggering haemorrhoid formation or worsening pre-existing haemorrhoids.
Conversely, frequent diarrhoea—another common Wegovy side effect—may irritate the anal area and contribute to inflammation, though this is a less established mechanism for haemorrhoid development.
Individual susceptibility varies considerably. Patients with pre-existing risk factors (previous haemorrhoids, chronic constipation, pregnancy history, or obesity itself) may be more vulnerable to developing symptomatic haemorrhoids whilst taking Wegovy. The medication does not directly damage anorectal tissue but may create conditions that facilitate haemorrhoid symptoms in predisposed individuals. If haemorrhoids develop during Wegovy treatment, addressing the underlying bowel habit changes is essential for management.
Proactive management of gastrointestinal side effects can significantly improve tolerability and may reduce the indirect risk of developing haemorrhoids. Patient education regarding expected side effects and practical strategies to minimise them is important.
Dietary modifications form the cornerstone of managing Wegovy-related digestive symptoms:
Increase fibre intake gradually through fruits, vegetables, whole grains, and legumes to promote regular, soft bowel movements
Maintain adequate hydration (approximately 6–8 glasses of fluid daily) to prevent constipation and reduce dehydration risk
Eat smaller, more frequent meals rather than large portions to reduce nausea and bloating
Avoid high-fat, fried, or heavily processed foods that may exacerbate gastrointestinal discomfort
Limit carbonated beverages that can increase bloating
For constipation specifically, which poses the greatest theoretical risk for haemorrhoid development:
Consider osmotic laxatives (e.g., macrogol) as first-line treatment, especially if bloating is present
Bulk-forming laxatives (e.g., ispaghula husk) may be helpful but use cautiously if experiencing bloating
Establish a regular toilet routine without prolonged sitting or straining
Increase physical activity, which promotes intestinal motility
Avoid constipating medications where possible (e.g., codeine, some antihistamines)
Some patients find that adjusting medication timing helps manage symptoms, though this is not specified in the SmPC. Discuss any timing adjustments with your prescriber.
Dose escalation should follow the recommended schedule in the SmPC strictly. If side effects become intolerable at a particular dose, the SmPC advises that dose escalation can be delayed by up to 4 weeks. If the 2.4 mg maintenance dose is not tolerated, a temporary reduction to 1.7 mg for up to 4 weeks may be considered.
Patients should maintain open communication with their healthcare team about side effects, as persistent or severe symptoms may require additional intervention or, rarely, treatment discontinuation.
Whilst haemorrhoids are common and often self-limiting, certain symptoms warrant prompt medical evaluation, particularly when occurring alongside Wegovy treatment.
Contact your GP or prescriber if you experience:
Rectal bleeding, even if minor—whilst haemorrhoids are a common cause, bleeding always requires assessment to exclude more serious colorectal pathology
Severe or persistent pain in the anal area that interferes with daily activities
A lump or swelling near the anus that does not resolve within a few days
Persistent constipation despite dietary modifications and over-the-counter laxatives
Signs of anaemia (fatigue, pallor, breathlessness) if bleeding has been ongoing
Severe, persistent abdominal pain, especially if radiating to the back (may indicate pancreatitis)
Yellowing of the skin or eyes (jaundice), which could indicate gallbladder problems
Seek urgent medical attention (contact 111 or attend A&E) if you develop:
Severe rectal bleeding with large amounts of blood
Excruciating anal pain suggesting thrombosed haemorrhoids or other acute anorectal conditions
Signs of infection (fever, increasing pain, purulent discharge)
Inability to pass stool (complete constipation) or severe abdominal pain
Severe abdominal pain with vomiting that could indicate pancreatitis (a rare but serious side effect of Wegovy)
Management approach: Your GP can diagnose haemorrhoids through history and examination. First-line treatment typically includes dietary advice, topical preparations (e.g., soothing ointments), and addressing underlying constipation. Persistent or unexplained rectal bleeding may require further investigation, including FIT (faecal immunochemical test) testing, in line with NICE guidance (NG12).
If haemorrhoids are clearly related to Wegovy-induced constipation, your prescriber may adjust your bowel management strategy or, in severe cases, discuss whether continuing Wegovy is appropriate.
Do not discontinue Wegovy without consulting your prescriber, as abrupt cessation may affect your weight management programme. Most haemorrhoid symptoms can be effectively managed whilst continuing treatment, provided the underlying bowel habit disturbance is addressed.
Regular follow-up appointments as part of your Wegovy treatment plan provide opportunities to discuss any developing symptoms, ensuring timely intervention and optimal treatment outcomes.
Wegovy does not directly cause haemorrhoids and they are not listed as an adverse reaction in the Summary of Product Characteristics. However, Wegovy-induced constipation (affecting approximately 24% of users) may indirectly increase haemorrhoid risk through straining during bowel movements, which elevates pressure in the haemorrhoidal venous plexus.
Prevent haemorrhoids by managing constipation through gradually increasing fibre intake, maintaining adequate hydration (6–8 glasses of fluid daily), establishing a regular toilet routine without prolonged sitting or straining, and using osmotic laxatives such as macrogol if needed. Regular physical activity also promotes healthy bowel function.
Contact your GP if you experience rectal bleeding (even if minor), severe or persistent anal pain, a lump near the anus that does not resolve, persistent constipation despite management, or signs of anaemia. Seek urgent medical attention for severe rectal bleeding, excruciating anal pain, signs of infection, or inability to pass stool.
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