Wegovy is a once-weekly injection that contains the active ingredient semaglutide. It belongs to a class of medicines known as GLP-1 receptor agonists and works by mimicking a natural hormone that regulates appetite. By acting on receptors in the brain, Wegovy helps you feel fuller sooner and reduces food cravings, making it easier to eat less.

Orlistat is a capsule taken with meals that works differently. Rather than affecting appetite, it blocks the enzyme lipase in your gut, preventing around one-third of the fat you eat from being absorbed. The unabsorbed fat passes through your body naturally.

Both medications support weight loss by reducing overall calorie intake, but they do so through different mechanisms. Your prescriber will recommend the most suitable option based on your medical history and weight loss goals.

Common side effects of Wegovy include nausea, vomiting, diarrhea, constipation, abdominal pain, headache, fatigue, and dizziness. Potential side effects of Orlistat include abdominal pain, oily spotting with bowel movements, gas with oily discharge, soft stools, fecal urgency, and vitamin deficiencies. Tell your doctor if these side effects persist or worsen.

In clinical trials, patients taking Wegovy saw a chnage of 12-15% in their body weight over 68 weeks. With Orlistat, typical weight loss is 3-5 lbs more than diet and exercise alone for up to a year. Amount of weight loss varies based on dosage, diet, exercise, and other factors. These medications are more effective when combined with lifestyle changes.

(Wilding et al, New England Journal of Medicine, 2021; 384:989-1002)

Wegovy has a stepped dosing plan that can be found on the product page, it is intended for chronic, long-term use alongside diet and exercise. Orlistat is also approved for long-term use. our prescribing team will advise you on the appropriate dose and length of therapy based on your progress and medical needs. 

No specific diet is recommended with Wegovy, but you should continue eating a well-balanced diet lower in calories, fat, and portions. With Orlistat, you will need to follow a low-fat diet to minimize gastrointestinal side effects. Avoid fatty or greasy foods and beverages. Check with your pharmacist if you have any food or drug interactions.

Once you have completed our online assessment and a prescriber has approved your treatment,  which includes a video consultation for weight loss medicines,  your medication is dispensed and dispatched via Royal Mail in discreet packaging.

Most orders are delivered within 1–3 working days, depending on your location. Delivery is free for orders over £50. You can track your order once it has been dispatched.

Injections and tablets work in fundamentally different ways, and the most suitable option depends on your circumstances. GLP-1 receptor agonist injections such as Wegovy (semaglutide) and Mounjaro (tirzepatide) act on appetite-regulating pathways in the brain, helping you feel full and reducing cravings. Clinical trials have shown average weight reductions of approximately 15–22% of body weight over 68–72 weeks, depending on the medication and dose.

Orlistat tablets work by blocking fat absorption in the gut and typically produce more modest weight loss,  around 2–3 kg more than diet and exercise alone over 12 months.

Your prescriber will recommend the most appropriate treatment based on your BMI, medical history, lifestyle, and weight loss goals. Some patients may prefer the convenience of a once-weekly injection, while others may favour a tablet-based approach.

Most patients begin to notice a reduction in appetite within the first 2–4 weeks of starting treatment with GLP-1 receptor agonist injections such as Wegovy or Mounjaro. Both medications use a gradual dose escalation schedule, meaning the full therapeutic effect builds over several weeks.

Measurable weight loss typically becomes apparent from around week 4–8, with more significant results seen between months 3 and 6 as you reach higher doses. Weight loss generally continues for 12–18 months before plateauing.

It is important to maintain realistic expectations and combine your medication with a balanced diet and regular physical activity for the best results. Your prescriber will monitor your progress and adjust your treatment as needed.

Switching from Mounjaro (tirzepatide) to Wegovy (semaglutide) is possible, but it should only be done under the supervision of a healthcare professional. The two medications contain different active ingredients and work on slightly different pathways. Mounjaro targets both GLP-1 and GIP receptors, while Wegovy acts on the GLP-1 receptor alone.

A washout period of at least 7 days between your last Mounjaro injection and your first Wegovy injection is generally recommended. You will typically start Wegovy at a low dose (0.25 mg) and titrate upwards gradually, even if you were on a higher dose of Mounjaro, to reduce the risk of side effects.

Common reasons for switching include changes in medication cost, supply issues, tolerability, or clinical response. If you are considering switching, speak to your prescriber, who can advise on the safest transition plan for your individual needs.

Yes. Wegovy (semaglutide), Mounjaro (tirzepatide), and prescription-strength Orlistat (120 mg) are all prescription-only medicines (POMs) in the UK. This means they can only be supplied following a clinical assessment by a qualified prescriber, such as a doctor or pharmacist.

A lower-strength version of Orlistat (60 mg) is available over the counter under the brand name Alli, but it is less effective than the prescription dose.

The prescription requirement exists because these medications are not suitable for everyone. A clinical assessment ensures that your chosen treatment is safe and appropriate for your health profile.

Weight loss injections such as Wegovy and Mounjaro have been extensively studied in large-scale clinical trials involving thousands of participants. They are approved by the MHRA (Medicines and Healthcare products Regulatory Agency) for use in the UK and are recommended by NICE (National Institute for Health and Care Excellence) for eligible patients.

Like all prescription medicines, they can cause side effects. The most commonly reported include nausea, vomiting, diarrhoea, and constipation, which are usually mild to moderate and tend to improve over time. More serious but rare side effects may include pancreatitis and gallbladder problems.

Your prescriber will carry out a thorough clinical assessment before prescribing to ensure the treatment is appropriate for you. Regular follow-up appointments help monitor your progress and manage any side effects.

Yes. All prescription weight loss medications,  including Wegovy, Mounjaro, and Orlistat,  are designed to be used alongside a reduced-calorie diet and increased physical activity. They are not intended as standalone treatments.

Clinical trials that demonstrated the effectiveness of these medicines required participants to follow a reduced-calorie diet and increase their physical activity levels. Medication supports your efforts by reducing appetite or fat absorption, but sustainable results depend on building healthier long-term habits.

The NHS recommends at least 150 minutes of moderate-intensity exercise per week. Your prescriber or pharmacist can offer guidance on dietary and lifestyle changes that complement your treatment.

Weight loss injections like Wegovy (semaglutide) and Mounjaro (tirzepatide) belong to a class of medicines called GLP-1 receptor agonists. They mimic a natural gut hormone called GLP-1, which signals to the brain that you are full. This reduces appetite, slows stomach emptying, and helps you eat less. Mounjaro additionally targets GIP receptors, which may contribute to its effects on metabolism and appetite.

Orlistat works differently. It inhibits the enzyme lipase in your digestive system, preventing approximately one-third of dietary fat from being absorbed. The undigested fat is then passed out of your body.

Both approaches help reduce overall calorie intake, but through different mechanisms. Your prescriber will explain which option is most suitable for you.

Prescription weight loss medicines are generally recommended for adults who have a BMI of 30 or above (classified as obese), or a BMI of 27 or above with at least one weight-related health condition such as type 2 diabetes, high blood pressure, or high cholesterol. BMI thresholds may be adjusted for people of certain ethnic backgrounds.

These treatments are intended for individuals who have been unable to achieve sufficient weight loss through diet and exercise alone. They are not suitable for everyone; for example, they are not recommended during pregnancy or breastfeeding or for individuals with certain medical conditions.

Our prescribers will assess your eligibility during the consultation process to ensure any recommended treatment is clinically appropriate for you.

Some weight loss medicines are available on the NHS, but access is limited and subject to strict eligibility criteria. Wegovy (semaglutide) is available through NHS specialist weight management services for eligible patients, and Mounjaro (tirzepatide) began a phased NHS rollout in England from March 2025 for patients with the highest clinical need,  initially those with a BMI of 40 or above and at least four weight-related health conditions.

NHS prescriptions typically require a referral from your GP to a specialist weight management service, and waiting times can vary significantly depending on your area.

Obtaining treatment through a registered online pharmacy such as Treat Discreet offers an alternative for patients who may not meet NHS criteria or who prefer not to wait. All treatments are prescribed by UK-registered prescribers following a thorough clinical assessment.

Wilding JPH, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. New England Journal of Medicine. 2021;384:989–1002. View study
Jastreboff AM, et al. Tirzepatide Once Weekly for the Treatment of Obesity. New England Journal of Medicine. 2022;387:205–216. View study
NICE Technology Appraisal Guidance TA875: Semaglutide for managing overweight and obesity. View guidance
NICE Technology Appraisal Guidance TA1026: Tirzepatide for managing overweight and obesity. View guidance
NHS England. Weight management injections. View page
MHRA. Summary of Product Characteristics: Wegovy (semaglutide 2.4 mg). View SmPC
MHRA. Summary of Product Characteristics: Orlistat 120 mg (Xenical). View SmPC