The trade-off nobody spells out

Most comparisons of these medicines stop at the weight-loss percentage, which is the least useful place to stop. The percentage tells you what happened on average to a trial group who met that trial's entry criteria and mostly stayed on treatment for a year or more. It does not tell you whether you will get on with a weekly pen, whether you can reliably take a tablet on an empty stomach before work, or whether you can afford the maintenance dose for as long as you would need it.

The honest version is that the options sit on a trade-off. The largest trial figures belong to the weekly tirzepatide injection. The tablets come in lower in the trials and remove the needle entirely. Where you land on that depends on things only you and your prescriber know.

Reading the trial numbers properly

Comparing across separate trials is a trap. Different trials enrol different people, run for different lengths and analyse the results in slightly different ways. SURMOUNT-1 ran for 72 weeks. STEP 1 ran for 68. OASIS 4 ran for 64. Those are not the same measurement.

That is why the head-to-head matters more than the rest. SURMOUNT-5 randomised 751 people to tirzepatide or semaglutide and followed them for 72 weeks, and reported a mean weight change of 20.2% against 13.7% (Aronne et al., 2025). Same people, same period, same yardstick.

One more thing worth knowing about averages. In SURMOUNT-1, 91% of people on the 15 mg dose lost at least 5% of their body weight, and 57% lost at least 20% (Jastreboff et al., 2022). The spread inside a trial group is wide. An average is the middle of a wide range, not a target.

The tablets are a genuinely new option

For years the choice was which injection. That changed. Oral semaglutide at 25 mg a day produced a mean weight change of 13.6% over 64 weeks in OASIS 4, against 2.2% on placebo (OASIS 4, 2025). The catch is how you take it: empty stomach, small sip of water, nothing else by mouth for a set period after. That suits some lives and not others.

Orforglipron is the other tablet, licensed in the United States as Foundayo. It is a small molecule rather than a peptide, which is why it gets absorbed without the timing rules. In ATTAIN-1, 3,127 people were randomised for 72 weeks, and the mean weight change at the highest dose studied was 11.2%, against 2.1% on placebo (Wharton et al., 2025). Lower than the injectable tirzepatide figures, and taken as a daily pill with no food rules. That is the trade in one sentence.

What it costs, where you are

Loading the cost information for where you are. Prices for these medicines are set locally, and the rules on who may publish them differ by country, so this section waits until it knows which country to answer for.

Ireland, and why the Wegovy pill being approved is not the same as it being available

Ireland gets its medicine licences the European way. The European Medicines Agency assesses, the European Commission grants an authorisation valid across the EU, and the HPRA is the national regulator that oversees it here. That is why Irish readers see the same brand names as UK readers: Mounjaro is Mounjaro, Wegovy is Wegovy.

On 15 July 2026 the European Commission approved the Wegovy pill, once-daily oral semaglutide 25 mg, for adults with obesity or with overweight and at least one weight-related condition. That authorisation covers Ireland. What it does not do is put the tablet in a pharmacy: Novo Nordisk said only that it intended to launch the pill in more countries during the second half of 2026, with no Irish date published, and reimbursement would then be a separate decision through the NCPE and the HSE rather than the HPRA.

So there are three gates, not one, and they are worth keeping straight: licensed, on sale, and paid for. Neither weekly injection is reimbursed by the HSE for weight management as of July 2026, which is why most Irish prescriptions for them are private.

Australia, and the missing price column

Australian readers get the same trial figures, the same dosing detail and the same side-effect warnings as everyone else, and no prices. That is not an oversight. The Therapeutic Goods Advertising Code lets pharmacies, practitioners approved under section 92 and pharmacy banner groups publish a price list for a prescription medicine. A site like this one is outside that exception, so the cost question is not offered on the tool when it is set to Australia and no figure appears on any card.

The TGA registers medicines; the PBS decides what is subsidised, and those are separate. Both weekly injections are registered for weight management. Neither is subsidised on the PBS for it: the PBS states that the sponsors of tirzepatide have not made a submission to list it for overweight or obesity, and in November 2025 the PBAC recommended listing semaglutide for people with established cardiovascular disease and obesity in certain circumstances, contingent on a price reduction and a risk-sharing arrangement, a listing that had not been completed as of July 2026.

Neither GLP-1 tablet is registered in Australia. Novo Nordisk lodged a TGA application for the 25 mg semaglutide tablet in May 2026 and Eli Lilly lodged one for orforglipron in January 2026, and the TGA had announced no decision on either. Anything sold to an Australian today as an oral GLP-1 is outside the TGA framework, which means nobody has checked what is in it.

Take this into the appointment, not instead of it

Every medicine on this page is prescription-only. Whether any of them is appropriate for you depends on your BMI, your other conditions, what you already take, whether you are pregnant or planning to be, your personal and family history, and a set of contraindications this page has no way of knowing about. Anything to do with doses, stepping up, stepping down or stopping is a question for the prescriber who supplied it.

What a page like this can do is get you into that conversation with better questions. If cost is the thing that will decide whether you can keep going for a year, say so. If needles are a genuine problem rather than a mild dislike, say that too. Those are the details that change what gets suggested.

If you want to see what any of this does to your own numbers over time, you can track weight, food and side effects free.