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Am I Eligible?

Trusted Online Pharmacy for Weight Loss

Fast review, often within 2 hours

If weight loss has felt harder than it should, you’re not alone.

4.7 37,000+ reviews
Am I Eligible? Explore Treatments
Your AI powered insights
  • Personalised plan, reviewed by clinicians
  • Treatments from £99, no long-term commitment
  • Ongoing support at every step of treatment
Fast review, often within 2 hours
  • Personalised plan, reviewed by clinicians
  • Treatments from £99, no long-term commitment
  • Ongoing support at every step of treatment
UK-registered pharmacy
Clinician-led prescribing
Speedy, discreet delivery

Mounjaro vs Wegovy at a glance

Both Wegovy and Mounjaro are once-weekly injections prescribed for weight loss. They're effective in different ways, and the right choice depends on how your body responds, not just the headline numbers.

Quick comparison

Mounjaro
Wegovy
How it works
GLP-1 + GIP hormones
GLP-1 hormone
Weight loss (studies)*
~20–22%
~15–20%
Dosing
Weekly injection
Weekly injection
Tolerability
Some people find dose increases easier
Well-established, varies by person
Typical cost
Often higher at equivalent doses
Often lower at equivalent doses

*Based on separate clinical trials. No direct head-to-head studies. Results vary.

How to choose

Choose Mounjaro if you want the strongest average results or may need help tolerating dose increases.

Choose Wegovy if you prefer a long-established GLP-1 option and respond well to it.

Both options are highly effective. The right choice depends on how your body responds, your budget, and how you tolerate dose changes.

If you're unsure, that's normal. Our clinicians help you compare, start safely, and switch if needed.

Understanding side effects

The most common early side effects. For most people it improves within the first few weeks as the body adjusts.

Nausea

"Will I feel sick all the time?"

Reality: The most common early side effect, particularly when starting or increasing your dose. For most people it settles within a few days to a couple of weeks as the body adjusts.

Diarrhoea & constipation

"What if my body reacts badly?"

Reality: Both are very common early on. Weight loss injections slow digestion, which can disrupt normal bowel patterns. They're usually manageable and improve as your body settles.

Bloating & burping

"Will I feel uncomfortable all the time?"

Reality: Bloating, gas and burping can occur as your digestive system adjusts to the medication. They're more common early in treatment and tend to ease over time.

Fatigue

"Why do I feel so drained?"

Reality: Fatigue is a common side effect of weight loss injections. It's not fully understood, but is likely linked to lower calorie intake, blood sugar changes, or disrupted sleep. It usually improves as your body adapts.

UK clinicians
Gradual dosing
Ongoing support
Treatment adjustments

It's not willpower. It's biology.

For years, we were told weight loss was simple: eat less, move more. But science now shows it's far more complex. Your hormones, genetics, and metabolism all play a role in how your body stores and burns fat.

01

Hormones regulate hunger

GLP-1 and GIP are hormones that tell your brain when you're full. Some people produce less of these signals, making it harder to feel satisfied after eating.

02

Genetics influence weight

Research shows that 40-70% of weight variation between people is due to genetic factors. Your genes affect metabolism, fat storage, and appetite regulation.

03

Treatments that work with your body

Modern weight loss medications mimic your body's natural hormones, helping restore the signals that regulate appetite and blood sugar.

See if treatment is right for you

Why choose Simple Online Pharmacy

We provide clinician-led weight loss support with clear guidance at every step. Our team reviews each consultation individually to ensure your treatment is safe and suitable.

3 M+

patients have trusted us

4.6 /5

Trustpilot rating

35 K+

patient reviews

Simple Online Pharmacy is fully registered with the GPhC and uses UK-registered clinicians.

Treatment on your terms

We believe you should be in control of your treatment, not locked into something that doesn't work for you.

No commitments

Order when you need to, not when we tell you to. You're always in control of your next order.

Simple reordering

When you're ready for your next dose, reordering takes seconds. Your details are saved, and our clinicians review every order to make sure it's still right for you.

Support if you want it

You can message our clinical team if side effects are hard to manage, your weight changes, or you’re unsure about your next dose. No pressure, no upselling.

What our expert says

For too long, people struggling with their weight have been told it's simply a matter of willpower. But the science tells a different story. Weight regulation is controlled by complex hormonal signals that vary from person to person.

Weight management is not solely about willpower. It is influenced by biological systems that regulate appetite and metabolism. Modern treatments work with these systems to support sustainable, healthier outcomes.

Aamina Rafiq, Clinical Pharmacist

Aamina Rafiq

Clinical Pharmacist

How to get started

Our simple process makes it easy to access the right treatment for you.

Complete a simple assessment

Answer questions about your health, lifestyle, and goals.

Your assessment is reviewed by a clinician

A UK-registered prescriber carefully reviews your assessment to ensure treatment is safe and suitable for you.

Receive discreet delivery

Your medication is dispensed by our registered pharmacy and delivered directly to your door in plain packaging.

Stay supported

Schedule reviews with our specialist teams to monitor your progress and provide support throughout your journey.

Choosing the right weight loss treatment

Understanding your options helps you make an informed decision with your clinician.

Injectable vs oral treatments: what's the difference?

Injectable weight loss treatments like Mounjaro and Wegovy work by mimicking hormones that regulate appetite and blood sugar. In clinical trials, they've shown higher average weight loss than tablet options, often in the range of 15-22% of body weight (results vary). Oral treatments can be a good option for people who prefer tablets or who aren't suitable for injections. They tend to produce more modest weight loss, but can still be effective as part of a broader plan. The right choice isn't just about results. Some people find a once-weekly injection fits easily into their routine, while others prefer a daily tablet. Your clinician will help you weigh up what's most suitable for your health and lifestyle.

How do clinicians decide which treatment is suitable?

Clinicians review your BMI, medical history, current medications, and any underlying health conditions before recommending a treatment. For injectable GLP-1 treatments, this usually means a BMI of 30 or above, or a BMI of 27 or above with a weight-related health condition, such as type 2 diabetes or high blood pressure. This isn't about gatekeeping. It's about safety. Some conditions, like a history of pancreatitis or medullary thyroid cancer, mean certain treatments aren't suitable. A proper assessment helps protect you and ensures the treatment has the best chance of working.

Why does dose titration matter?

Most weight loss injections start at a low dose and increase gradually over several weeks. This process, known as dose titration, helps your body adjust and reduces the chance of side effects such as nausea. Increasing the dose too quickly doesn't speed up weight loss. It usually just makes side effects harder to manage. People who follow the recommended titration schedule tend to stay on treatment longer and see better results over time.

When does switching treatments make sense?

Sometimes a treatment that worked well at first becomes less effective, or side effects don't settle as expected. In these cases, switching to something different (for example from Wegovy to Mounjaro, or to an oral option) can be helpful. Our clinicians monitor how you're responding and can suggest changes if your current plan isn't delivering. Adjusting treatment is a normal part of long-term weight management, and there's no one-size-fits-all approach.

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Weight loss FAQs

Common questions about weight loss treatments and our service.

Which weight loss treatment is best for me?

The right treatment depends on your health, BMI, medical history, and personal preferences. Our clinicians will review your assessment to recommend the most suitable option.

Do I need a prescription for weight loss medication?

Yes, all effective weight loss medications in the UK require a prescription. Our clinicians will assess your suitability and issue a prescription if appropriate.

How much weight can I expect to lose?

Results vary between individuals and treatments. Injectable treatments like Mounjaro and Wegovy typically show higher weight loss percentages than oral medications. Your clinician can discuss realistic expectations.

Are weight loss injections safe?

GLP-1 injections like Mounjaro and Wegovy have been through extensive clinical trials and are approved for use in the UK. Like all medications, they have potential side effects which your clinician will discuss with you.

How long do I need to take weight loss medication?

Treatment duration varies. Some people use medication for a set period to reach their goal weight, while others may benefit from longer-term use. Your clinician will review your progress regularly.

Can I get weight loss treatment on the NHS?

Some weight loss treatments are available through NHS specialist services, but eligibility criteria are strict. Private services like ours offer an alternative with faster access.

Aamina Rafiq

Reviewed by

Aamina Rafiq

Clinical Pharmacist

This page has been reviewed by our clinical team to ensure it is clear, accurate, and up to date.

Last updated: 10 February 2026