This article is for information only. All three are prescription medicines, and only a doctor can judge which fits. Nothing here is medical advice.
One family, three generations
Saxenda, Wegovy and Mounjaro all suppress appetite through GLP-1 signalling. Because the underlying mechanism is shared, so is the side-effect profile. What differs is how long each drug acts and how many hormones it touches.
The differences at a glance
- •Saxenda (liraglutide) — daily injection, GLP-1 only, about 8% average weight loss in trials
- •Wegovy (semaglutide) — weekly injection, GLP-1 only, about 14.9%
- •Mounjaro (tirzepatide) — weekly injection, GLP-1 plus GIP, about 20.9%
Mounjaro leads on the numbers, but a bigger drop also means a faster change for the body to absorb. Tolerance for side effects, other conditions and cost all belong in the same decision.
What they share
- •Digestive symptoms — nausea, vomiting, diarrhoea, constipation — are the most common effect of all three
- •Pancreatitis and gallbladder problems are rare but class-wide risks
- •All three are contraindicated with a history of medullary thyroid carcinoma or MEN2
- •All three come with muscle loss, so protein and resistance training matter
- •Stopping usually brings appetite, and much of the weight, back
What the drug does not do for you
In every one of these trials, participants also received diet and exercise counselling. The headline percentages are not what happens when a drug is the only thing that changes.
The medicine quiets appetite. What you eat is still your decision, and the habits you build while appetite is quiet are what remain when it returns.
On these drugs or off them, writing down what you eat shows you what actually changed. It matters more here, not less — suppressed appetite makes it easy to end up eating too little of the things you need.
The decision belongs in a consultation
Weight, age, other conditions, current medication, side-effect history and what you can afford all differ. Reviews and before-after numbers online are context, not a prescription.
Products sold without a prescription cannot be verified as genuine and are illegal in most places. Go through a clinic.