What are gallstones?
Gallstones are hard deposits that form in your gallbladder, a small pear-shaped organ beneath your liver that stores bile for digestion. These deposits range from tiny grains to golf ball-sized stones.
In the UK, gallstones affect approximately 10-15% of adults, with women twice as likely as men to develop them.
Most people with gallstones (about 80%) never experience symptoms; these are called ‘silent stones’ and typically don’t require treatment.
There are two main types of gallstones:
- Cholesterol stones (80% of cases): Formed when bile contains too much cholesterol
- Pigment stones (20% of cases): Formed when bile contains excess bilirubin
Risk factors and symptoms
Several factors increase your risk of developing gallstones:
| Risk Factor |
Increases Risk By |
| Female sex |
2-3× higher than males |
| Age over 40 |
4× higher than under 40 |
| Obesity (BMI >30) |
3× higher than normal weight |
| Rapid weight loss |
3-5× higher during active weight loss |
| Family history |
2× if first-degree relative affected |
| Certain medications |
Varies by medication |
When gallstones cause symptoms, they typically include:
- Sharp pain in the upper right abdomen that may radiate to your back or shoulder
- Nausea or vomiting
- Fever or chills (if infection develops)
- Yellowing of skin and eyes (jaundice) if stones block the bile ducts
- Indigestion, bloating, or heartburn
What is Wegovy?
Wegovy is an injectable weight-loss medication containing the drug semaglutide, a GLP-1 receptor agonist that helps regulate appetite and food intake.
It was approved in the UK in 2023 for weight management in adults with:
- BMI ≥30 kg/m² (obesity), or
- BMI ≥27 kg/m² (overweight) with at least one weight-related condition
The medication works in several ways:
- Reduces hunger signals by acting on the brain’s appetite control centre
- Slows stomach emptying, creating longer-lasting fullness after meals
- Reduces food cravings, particularly for ultra-processed foods
Clinical trials show that people taking Wegovy lose an average of 15% of their body weight after 68 weeks, compared to 2.4% with placebo. For someone weighing 100kg, that’s approximately 15kg of weight loss.
Wegovy is taken once a week, with a gradual dose increase over 16-20 weeks to minimise side effects.
Wegovy and gallstone risk
Research suggests that Wegovy slightly increases the risk of gallbladder problems, including gallstones. In clinical trials:
- 2.5% of Wegovy users developed gallbladder-related disorders
- 1.0% of placebo users developed similar problems
- Gallstones specifically occurred in 1.6% of Wegovy users vs. 0.7% on placebo
This increased risk occurs through two main mechanisms:
- Rapid weight loss effect: When you lose weight quickly, your liver secretes extra cholesterol into bile, which can form stones. This happens with any rapid weight loss method, not just Wegovy.
- Direct medication effect: GLP-1 medications like Wegovy can slow gallbladder emptying, potentially increasing the risk of bile stasis and stone formation.
Comparing gallstone risk across weight loss methods
| Weight Loss Method |
Approximate Gallstone Risk |
Notes |
| Wegovy (semaglutide) |
2.5% |
Most cases are mild to moderate |
| Mounjaro (tirzepatide) |
2.3% |
Similar risk profile to Wegovy |
| Very low-calorie diet |
10-25% |
Significantly higher risk than medications |
| Bariatric surgery |
30-45% |
The highest risk of all weight loss methods |
| Gradual lifestyle changes |
1-2% |
Lowest risk approach |
Safe usage guidelines
If you have gallstones or are at high risk for developing them, these strategies can help you use Wegovy more safely:
Lose weight slowly
The faster you lose weight, the higher your risk of developing gallstones. Aim for:
- 0.5-1kg (1-2 pounds) per week, maximum weight loss
- Avoid very low-calorie diets while on Wegovy
- Consider slower dose escalation (discuss with your doctor)
Maintain adequate dietary fat
Contrary to popular belief, extremely low-fat diets can actually increase gallstone risk by reducing gallbladder contractions:
- Include moderate amounts of fat from whole foods in your meals
- Focus on fats from whole foods like olive oil, avocados, nuts, meat, and oily fish
- Avoid erratic eating patterns with long fasting periods
Stay well-hydrated
Proper hydration helps maintain proper bile flow and may reduce stone formation:
- Drink 2-3 litres of water daily (around 8-10 glasses)
- Limit alcohol, which can increase gallstone risk
- Consider adding lemon to water (citrus may help prevent stones)
Consider preventive measures
For those at very high risk, your doctor might recommend:
- Ursodeoxycholic acid (sometimes prescribed to prevent gallstone formation)
- More frequent monitoring via ultrasound
- Slower Wegovy dose titration schedule
Monitoring recommendations
When taking Wegovy with existing gallstones or high gallstone risk, monitoring is essential:
Know the warning signs
Contact your doctor immediately if you experience:
- Severe pain in your upper right or middle abdomen, especially after meals
- Pain that radiates to your back or right shoulder
- Fever, chills, or yellowing of skin/eyes
- Persistent nausea or vomiting
- Tea-colored urine or light-colored stools
Establish a monitoring plan
Work with your healthcare provider to create an appropriate monitoring schedule:
- Baseline ultrasound before starting Wegovy (if you have known gallstones)
- Regular liver function tests during treatment
- Follow-up ultrasound if symptoms develop
- Regular check-ins with your healthcare provider
NHS considerations
NHS eligibility and access
Having gallstones does not automatically disqualify you from NHS-prescribed Wegovy, but:
- Your GP or specialist should be aware of your gallstone history
- NHS guidelines recommend careful monitoring for those with gallbladder disease
- You may be referred to a gastroenterologist for concurrent management
Private prescription options
If you don’t meet NHS criteria, a private prescription is an option:
- Second Nature offers Wegovy with comprehensive support and monitoring
- Private prescribers should be informed of your gallstone history
- Expect to pay £149-£249 monthly for medication and support from a registered dietitian
Frequently asked questions
Will Wegovy make my existing gallstones worse?
Wegovy doesn’t necessarily worsen existing gallstones if you lose weight slowly, eat a diet based on whole foods, and stay hydrated.
Still, it’s essential to maintain regular monitoring with your doctor or healthcare provider.
Can I take Wegovy after gallbladder removal?
Yes, you can take Wegovy if you’ve had your gallbladder removed (cholecystectomy). In fact, you may have a lower risk of gallstone-related complications since the primary site of stone formation is gone.
However, you might still experience digestive side effects from Wegovy that could be confused with post-cholecystectomy syndrome, so discuss this with your doctor.
What should I do if I get stomach pain while taking Wegovy?
If you develop upper right abdominal pain while taking Wegovy, don’t ignore it. Contact your healthcare provider immediately, as this could indicate gallbladder problems.
Be specific about the location, severity, and timing of your pain. While waiting for medical advice, stop eating, stay hydrated with clear fluids, and avoid fatty foods.
Is Mounjaro safer than Wegovy for people with gallstones?
Current evidence suggests Mounjaro (tirzepatide) has a similar gallstone risk profile to Wegovy.
Clinical trials show a 2.3% incidence of gallbladder problems with Mounjaro versus 2.5% with Wegovy, which is not a significant difference. Both medications require the same precautions if you have gallstones.
Should I get my gallbladder removed before starting Wegovy?
Preventive gallbladder removal is not recommended solely for starting Wegovy. Surgery carries its own risks and is typically only recommended for symptomatic gallstones.
If you have silent gallstones, most doctors will recommend monitoring rather than surgery before starting weight loss treatment.
Take home message
You can take Wegovy if you have gallstones, but you should work with your doctor to develop a monitoring plan and take precautions to minimise risks.
The small increased risk of gallbladder problems with Wegovy (2.5% vs 1% with placebo) should be viewed in context; it’s significantly lower than with very low-calorie diets or bariatric surgery, and most cases are mild to moderate.
By losing weight gradually (0.5-1kg weekly), staying well-hydrated, maintaining moderate healthy fat intake, and monitoring for warning signs, most people with gallstones can safely benefit from Wegovy treatment.
The health benefits of achieving a healthy weight with Wegovy typically outweigh the small increased gallstone risk for most people.
Always discuss your personal risk factors with your healthcare provider to make an informed decision.
Second Nature's Mounjaro and Wegovy programmes
Second Nature provides Mounjaro or Wegovy as part of our Mounjaro and Wegovy weight-loss programmes.
Why choose Second Nature over other medication providers, assuming you're eligible?
Because peace of mind matters.
We've had the privilege of working with the NHS for over eight years, helping people across the UK take meaningful steps toward a healthier, happier life.
Our programmes are designed to meet people where they are, whether that means support with weight loss through compassionate one-to-one health coaching, or access to the latest weight-loss medications (like Mounjaro and Wegovy) delivered alongside expert care from a multidisciplinary team of doctors, psychologists, dietitians, and personal trainers.
At the heart of everything we do is a simple belief: real, lasting change comes from building better habits, not relying on quick fixes. We're here to support that change every step of the way.
With over a decade of experience, thousands of lives changed, and a long-standing record of delivering programmes used by the NHS, we believe we're the UK's most trusted weight-loss programme.
We hope to offer you something invaluable: peace of mind, and the support you need to take that first step.
