In short: In the UK, medicines for weight management now come as weekly injections (semaglutide, tirzepatide), a daily injection (liraglutide) and daily tablets (oral semaglutide, orforglipron and orlistat). The GLP-1 based injections and tablets reduce appetite, while orlistat reduces how much fat you absorb from food. No single option is right for everyone: the choice depends on your health, other medicines, preferences and how you tolerate treatment, and a prescriber must decide what is suitable.

This guide, written by a Ready Health prescribing pharmacist in Standish, compares the main options so you can have an informed conversation with your clinician.

How do weight-management injections work?

Injectable GLP-1 based medicines mimic gut hormones that act on appetite centres in the brain and slow stomach emptying. Most people feel fuller sooner and eat less. They are injected just under the skin with a pen, either weekly (semaglutide, tirzepatide) or daily (liraglutide), and the dose is increased gradually. Learn more about tirzepatide and semaglutide.

What weight-management tablets are available in the UK?

Oral semaglutide (weight-management strength): approved by the MHRA in June 2026. Taken once daily on an empty stomach with a small sip of water, followed by a wait of at least 30 minutes before eating, drinking or taking other medicines.
Orforglipron: a non-peptide GLP-1 tablet authorised in August 2026. Taken once daily, with no food or water restrictions. Read our guide to orforglipron.
Orlistat: taken with meals, it blocks some of the fat in food from being absorbed. A higher strength is prescription-only; a lower strength can be sold by pharmacies under a pharmacist's supervision to adults with a BMI of 28 or more.

How do injections and tablets compare?

Option	How often	How it works	Points to consider
Weekly GLP-1 based injection	Once a week	Reduces appetite	Largest average weight loss in trials; digestive side effects common at first; needs a pen and fridge storage
Daily GLP-1 injection (liraglutide)	Once a day	Reduces appetite	Daily injections; generally smaller average effect than weekly options
Oral semaglutide	Once a day	Reduces appetite	No needles; strict empty-stomach routine each morning
Orforglipron	Once a day	Reduces appetite	No needles; no food or water restrictions; newer medicine with less real-world experience
Orlistat	With each main meal	Reduces fat absorption	Modest average effect; oily or loose stools if meals are high in fat; may affect absorption of some vitamins and medicines

Average results from clinical trials differ between medicines and trials are not always directly comparable. Individual responses vary widely.

What side effects should I consider?

GLP-1 based medicines (injections and tablets): nausea, vomiting, diarrhoea, constipation and indigestion are common, especially during dose increases. Rare but serious risks include acute pancreatitis and gallbladder problems. They should not be used in pregnancy or breastfeeding, and effective contraception is advised.
Orlistat: digestive effects such as oily stools, urgency and wind, particularly after fatty meals. A multivitamin taken at bedtime may be advised, and orlistat can interact with medicines including some contraceptive pills (if it causes severe diarrhoea), levothyroxine, warfarin and some epilepsy medicines.

How do I choose between an injection and a tablet?

Questions your prescriber may discuss with you include:

your BMI and any weight-related conditions, such as type 2 diabetes or high blood pressure
your medical history, including pancreatitis, gallbladder or bowel problems and eating disorders
other medicines you take and whether a daily tablet routine could affect them
whether you are comfortable using a pen, and whether you can store medicine in a fridge
pregnancy plans and contraception
how you have responded to any previous treatment

Frequently asked questions

Are injections more effective than tablets?

On average, weekly GLP-1 based injections have shown the largest weight loss in trials, but the newer daily GLP-1 tablets also produce meaningful results for many people. Direct comparisons are limited.

Can I buy weight-loss tablets over the counter?

Only low-strength orlistat can be sold by a pharmacy without a prescription, after a pharmacist's assessment. GLP-1 tablets are prescription-only.

Can I switch from an injection to a tablet?

Sometimes. Switching needs planning with a prescriber, who will advise on timing and starting dose.

Do I still need to change my diet and activity?

Yes. All of these medicines are licensed for use alongside a reduced-calorie diet and increased physical activity.

Key takeaways

UK options include weekly and daily injections and several daily tablets.
GLP-1 based medicines reduce appetite; orlistat reduces fat absorption.
Each option has different routines, side effects and suitability criteria.
A prescriber should help you weigh up the options based on your health.

Sources and further reading

Last reviewed: October 2026 by Shamir Patel, Independent Prescribing Pharmacist, Ready Health. This article is general information and does not replace advice from your own clinician.

If you would like help understanding your options, you can book a weight-management consultation at Ready Health in Standish, Wigan. A prescriber will assess your health and discuss which approaches, if any, are suitable for you.

Injections or Tablets for Weight Management: How the Options Compare