Phlo Clinic - GLP-1 Guide

About this tool This tool provides general educational information about oral and injectable GLP-1 medicines. It does not assess suitability for treatment, provide treatment recommendations, determine eligibility, recommend dose changes, or advise whether a medicine should be started, stopped, continued or switched.

To get started

Are you currently on a GLP-1 medicine?

Question 1 of 2

What would you like to learn about?

Question 1 of 3

Which medicine are you currently on?

Question 2 of 3

What's your main interest in oral GLP-1 medicines?

Question 3 of 3

Are you interested in learning about longer-term maintenance options?

Some people on GLP-1 medicines are interested in whether oral options might suit a maintenance phase once their goal weight is reached.

ℹ️ Information for people in a similar situation

A Phlo pharmacist can talk through all of these options with you.

This tool is for educational purposes only — not a prescription or clinical decision. This tool provides general information about GLP-1 medicines. It does not assess your suitability for treatment, make treatment recommendations, or advise whether a medicine should be started, stopped, continued or switched. Any change to your treatment must be discussed with and approved by a Phlo pharmacist or clinician before it takes effect.

If you feel unwell, have severe abdominal pain, or are concerned about a side effect, contact your Phlo clinician or NHS 111.

ℹ️ Information about injectable GLP-1 medicines

About injectable GLP-1 medicines

Injectable GLP-1 medicines are given as a once-weekly injection. The two currently licensed for weight management in the UK are Mounjaro (tirzepatide) and Wegovy (semaglutide).

→Clinical trials show average weight loss of around 15% with Wegovy and around 22.5% with Mounjaro at the highest dose. Individual results vary.

→Both are self-administered using a pre-filled pen, once a week, on any day of your choice.

→Common side effects include nausea, vomiting, and diarrhoea — particularly during dose escalation. These often reduce over time.

→A clinician assessment is required to determine which medicine, if any, is appropriate for your circumstances.

Find out more

This tool is for educational purposes only. This information does not constitute medical advice and does not determine whether any treatment is suitable for you. Always consult a qualified Phlo clinician before starting any treatment.

Clinical trial references Figures are mean averages from pivotal phase 3 trials and will vary between individuals. · Mounjaro ~22.5% (highest dose, efficacy estimand) — SURMOUNT-1. Jastreboff et al. N Engl J Med 2022;387:205–216. · Wegovy ~15% — STEP 1. Wilding et al. N Engl J Med 2021;384:989–1002.

ℹ️ Information about oral GLP-1 medicines

About oral GLP-1 medicines

Oral GLP-1 medicines are taken as a once-daily tablet. They offer an alternative for people who prefer not to self-inject. Clinical trials have shown meaningful weight loss results, though average outcomes are somewhat lower than injectable options.

→Wegovy Tablet trials show average weight loss of around 13–14%. Individual results vary.

→Oral GLP-1 medicines carry similar gastrointestinal side effect risks to injectable versions — nausea, vomiting and diarrhoea are common, particularly early on.

→A clinician assessment is required to determine which medicine, if any, is appropriate for your circumstances.

Find out more

This tool is for educational purposes only. This information does not constitute medical advice and does not determine whether any treatment is suitable for you. Always consult a qualified Phlo clinician before starting any treatment.

Clinical trial references Figures are mean averages from pivotal phase 3 trials and will vary between individuals. · Wegovy Tablet (oral semaglutide) ~13–14% — OASIS 1 (Knop et al. Lancet 2023) and OASIS 4 (N Engl J Med 2025).

ℹ️ Comparing oral and injectable GLP-1 medicines

How oral and injectable GLP-1 medicines differ

Both oral and injectable GLP-1 medicines work in a similar way — they reduce appetite and slow digestion. The main differences are in how they're taken, average efficacy in trials, and practical considerations around routine.

→Injectable options (Mounjaro, Wegovy) — once weekly. Trial data shows average weight loss of 15–22.5% depending on medicine and dose. Both licensed for use in the UK.

→Wegovy Tablet — once daily. Trials show average weight loss of around 13–14%. Coming soon to the UK.

→All GLP-1 medicines carry a risk of gastrointestinal side effects. The differences in average efficacy between oral and injectable options are one of several factors clinicians and patients consider together.

→A clinician assessment is required to determine which medicine, if any, is appropriate for you.

Find out more

This tool is for educational purposes only. This information does not constitute medical advice and does not determine whether any treatment is suitable for you. Always consult a qualified Phlo clinician before starting any treatment.

Clinical trial references Figures are mean averages from pivotal phase 3 trials and will vary between individuals. · Mounjaro ~22.5% (highest dose, efficacy estimand) — SURMOUNT-1. Jastreboff et al. N Engl J Med 2022;387:205–216. · Wegovy ~15% — STEP 1. Wilding et al. N Engl J Med 2021;384:989–1002. · Wegovy Tablet (oral semaglutide) ~13–14% — OASIS 1 (Knop et al. Lancet 2023) and OASIS 4 (N Engl J Med 2025).

Oral and injectable GLP-1 medicines