Weight loss injections — Mounjaro, Wegovy and Saxenda — are the biggest change in weight management in a generation, with trial participants losing 15–22% of body weight. They're also widely mis-sold online, under-monitored, and stopped too casually. This guide gives you the straight facts: how they work, what they genuinely cost in the UK, who qualifies, and what safe, GP-supervised treatment looks like at The Vesey's weight loss clinic in Sutton Coldfield.
How GLP-1 Weight Loss Injections Work
Mounjaro (tirzepatide) and Wegovy (semaglutide) mimic gut hormones — GLP-1, and for tirzepatide also GIP — that regulate appetite. Injected once weekly, they slow stomach emptying and act on the brain's appetite centres, so you feel full sooner and food noise quietens. Saxenda (liraglutide) works similarly but is injected daily and is generally less effective.
The results in trials are unprecedented for medication: average weight loss of around 15% of body weight with Wegovy and up to 22.5% with Mounjaro at the highest dose over 72 weeks — approaching bariatric surgery territory. Alongside weight, they improve blood sugar, blood pressure and cholesterol; semaglutide has also shown a 20% reduction in major cardiovascular events in people with existing heart disease.
They are not magic: they work while you take them, and the best outcomes come from pairing medication with permanent changes to diet, strength training and sleep — which is exactly what a supervised programme is for.
Who Qualifies and What It Costs
UK licensing broadly covers adults with a BMI of 30+, or 27+ with a weight-related condition (type 2 diabetes, high blood pressure, sleep apnoea, PCOS). Lower thresholds apply for some ethnic groups at higher metabolic risk. NHS access exists but remains tightly rationed with long waits, which is why most people currently access treatment privately.
Realistic private costs: medication typically runs £120–£250 per month depending on the drug and dose (doses step up gradually over the first months). At The Vesey, treatment starts with a full assessment from £200 including baseline blood tests, medication is quoted transparently at assessment, and monthly monitoring from £100 covers dose titration, side-effect management and progress reviews with a GP.
Beware pharmacies and websites selling injections after a two-minute questionnaire with no bloods, no baseline weight verification and no follow-up. The medication is the easy part; the medicine is in the monitoring.
Side Effects and Safety
Common and usually manageable: nausea, constipation or diarrhoea, and reflux, mostly during dose increases, settling with slower titration and dietary adjustments. Less common but important: gallstones (faster with rapid weight loss), pancreatitis (rare — seek help for severe persistent abdominal pain), and dehydration. GLP-1s aren't used in pregnancy, when trying to conceive, or with a personal/family history of medullary thyroid cancer.
Two under-discussed issues: muscle loss — a meaningful share of weight lost is lean mass unless you eat adequate protein and strength-train, which matters enormously for long-term metabolic health; and rebound — stopping abruptly without an exit plan sees most people regain much of the weight within a year. A good clinic plans for maintenance from day one, not as an afterthought.
This is also why baseline bloods matter: checking liver and kidney function, HbA1c, lipids and thyroid before starting means treatment decisions are made on your physiology, not a website form.
Starting Safely at The Vesey
Our GP-led weight loss clinic in Sutton Coldfield starts with a proper assessment (from £200 including baseline bloods): medical history, medication review, weight and metabolic profile, and an honest conversation about whether injections are right for you — including when the answer is no.
Ongoing care includes monthly GP monitoring (from £100), dose titration, protein and strength-training guidance, dietitian support, and a structured maintenance plan for coming off medication without rebound. No NHS waiting list, same-week appointments, 7 days a week. Book online or call 0121 387 3727.
GP-supervised weight loss — assessment with baseline bloods
CQC-regulated · Rated 4.87/5 on Doctify · Open 7 days 8am–8pm · No referral needed
Frequently Asked Questions
How much do weight loss injections cost in the UK?
Privately, medication typically costs £120–£250 per month depending on drug and dose. At The Vesey, assessment is from £200 including baseline blood tests, with medication quoted transparently at assessment and monthly GP monitoring from £100. Be wary of prices that seem too good — they usually omit monitoring entirely.
Which is better — Mounjaro or Wegovy?
Trial data shows greater average weight loss with Mounjaro (up to 22.5% of body weight) than Wegovy (around 15%), and head-to-head data confirms the advantage. But tolerability, your medical history, availability and cost all matter — the right choice is individual and best made at a medical assessment.
Do I qualify for weight loss injections?
Broadly: BMI 30+, or 27+ with a weight-related condition such as type 2 diabetes, hypertension, sleep apnoea or PCOS. A proper assessment also screens for reasons not to use them, including pregnancy plans, pancreatitis history and certain thyroid cancers.
Will I regain weight when I stop the injections?
Without a plan, most people regain a substantial portion within a year — appetite returns when the medication stops. Regain is not inevitable: gradual tapering, protein targets, strength training and structured maintenance support dramatically improve long-term results, which is why The Vesey builds the exit plan in from the start.