Semaglutide as a tablet and as an injection gave a similar weight loss in trials, but the tablet needs dozens of times more substance. From a tablet about 1 percent of the semaglutide reaches the blood, and from a subcutaneous injection about 89 percent. That is why the tablet is taken at 25 or 50 mg every day, and the injection at 2.4 mg once a week. Below we compare both forms in figures from the OASIS, PIONEER and STEP trials.
How much weight do you lose on the tablet and on the injection?
No direct comparison of the two forms in a single trial has been published so far. However, trials of similar design and length can be set side by side. A review of 30 papers from August 2026 rated the effectiveness of both forms as comparable.
| Trial | Form and dose | Duration | Weight loss | Placebo |
|---|---|---|---|---|
| OASIS 1 | tablet 50 mg daily | 68 weeks | 15.1 percent | 2.4 percent |
| OASIS 4 | tablet 25 mg daily | 64 weeks | 13.6 percent | 2.2 percent |
| STEP 1 | injection 2.4 mg once a week | 68 weeks | 14.9 percent | 2.4 percent |
The 50 mg tablet and the 2.4 mg injection gave an almost identical result after 68 weeks. An analysis from April 2026 showed that 82.2 percent of people on the 25 mg tablet reached blood levels similar to those on the 2.4 mg injection.
Why does the tablet need so much more substance?
Semaglutide is a peptide, and peptides are poorly absorbed in the stomach. The tablet therefore contains a substance that helps absorption, called SNAC. Even so, about 1 percent of the dose reaches the blood from the tablet. In an analysis of 5 and 10 mg tablets taken as recommended it was 0.8 percent.
| Comparison | Tablet 25 mg | Tablet 50 mg | Injection 2.4 mg |
|---|---|---|---|
| Amount of semaglutide per week | 175 mg | 350 mg | 2.4 mg |
| Absorption into the blood | about 1 percent | about 1 percent | about 89 percent |
| How often | daily | daily | once a week |
The 25 mg tablet uses about 73 times more semaglutide per week than the 2.4 mg injection. The 50 mg tablet uses almost 146 times more. With the injection almost the whole dose reaches the blood, while with the tablet almost all of it passes through the digestive tract without being absorbed.
How must the tablet be taken?
The tablet only works if the rules for taking it are followed strictly. A pharmacokinetic analysis from 2021 described the conditions recommended in the trials: the tablet is swallowed with at most 120 ml of water, and then nothing is eaten for 30 minutes. Waiting longer increased absorption, and more water reduced it.
The same analysis measured how much absorption varies from day to day in the same person. The variability was 137 percent for a single dose. Thanks to daily dosing and the long action of semaglutide, the variability of the blood level fell to 33 percent. With a once-weekly injection this problem does not exist.
Which form is better tolerated?
Both forms cause similar complaints, mainly from the digestive tract. In OASIS 1, gastrointestinal complaints were reported by 80 percent of people on the 50 mg tablet and 46 percent on placebo. In OASIS 4, with the 25 mg tablet, it was 74.0 percent against 42.2 percent.
In STEP 1, on the 2.4 mg injection, the most common complaints were nausea and diarrhoea, usually temporary. 4.5 percent of people stopped treatment because of stomach complaints. The 2026 review notes that some people prefer the tablet because they are afraid of needles.
How does the tablet work in type 2 diabetes?
Most PIONEER trials in diabetes used lower tablet doses, up to 14 mg a day. In PIONEER 4 the 14 mg tablet lowered glycated haemoglobin by 1.2 points after 26 weeks. A liraglutide 1.8 mg injection lowered it by 1.1 points, and placebo by 0.2 points.
Body weight fell by 4.4 kg on the tablet, by 3.1 kg on liraglutide and by 0.5 kg on placebo. The semaglutide 1 mg injection lowered glycated haemoglobin by 1.55 to 1.8 points in the SUSTAIN trials. The results of the injection in diabetes are described in the guide on semaglutide and the SUSTAIN trials.
The PIONEER PLUS trial from 2023 tested higher tablet doses in 1606 people with diabetes. After 52 weeks glycated haemoglobin fell by 1.5 points at 14 mg, by 1.8 points at 25 mg and by 2.0 points at 50 mg. However, the higher doses caused gastrointestinal complaints more often.
Which to choose: tablet or injection?
A once-weekly injection gives a similar effect using a fraction of the substance and without daily rules for taking it. The tablet is convenient for people who do not want to inject, but it has to be taken every day on an empty stomach. The list collects the most important differences.
- Injection: once a week, about 89 percent absorption, no rules about meals.
- Tablet: daily, about 1 percent absorption, on an empty stomach and with a little water.
- Effectiveness: the 50 mg tablet and the 2.4 mg injection gave almost the same weight loss in trials.
- Complaints: similar with both forms, mainly nausea and diarrhoea.
The differences between routes of administration of peptides in general are described in the guide on peptide routes of administration. Preparing a solution from a vial is shown in the guide on how to reconstitute peptides.
Where to buy semaglutide for injection?
The shop offers semaglutide 3 mg Bio-Peptide in a vial for injection, for 90 EUR, in stock. At a dose of 2.4 mg a week one vial lasts a week and two days. The doses in the following weeks and their results are described in the guide on semaglutide doses in trials.
The products in the shop are material for laboratory research, not the medicines Wegovy, Ozempic or Rybelsus. Treatment decisions are made by a doctor. All information about the molecule is collected on the semaglutide page.
Frequently asked questions
Does the semaglutide tablet work the same as the injection?
In trials it gave a similar weight loss: 15.1 percent with the 50 mg tablet in OASIS 1 and 14.9 percent with the 2.4 mg injection in STEP 1, in both cases after 68 weeks.
Why is the dose in the tablet so high?
From a tablet about 1 percent of the semaglutide reaches the blood, and from an injection about 89 percent. That is why the tablet contains 25 or 50 mg and is taken every day.
How should the semaglutide tablet be taken?
In trials it was swallowed with at most 120 ml of water, and then nothing was eaten for 30 minutes. More water reduced absorption.
Which form has fewer side effects?
Both cause similar complaints, mainly nausea and diarrhoea. In OASIS 1, 80 percent of people on the 50 mg tablet had stomach complaints.
How much semaglutide does the tablet use compared with the injection?
The 25 mg tablet uses 175 mg a week, about 73 times more than the 2.4 mg once-weekly injection.
Sources
- Knop FK, Aroda VR, do Vale RD et al. Oral semaglutide 50 mg taken once per day in adults with overweight or obesity (OASIS 1). The Lancet, 2023, 402(10403): 705-719. https://doi.org/10.1016/S0140-6736(23)01185-6
- Wharton S, Lingvay I, Bogdanski P et al. Oral Semaglutide at a Dose of 25 mg in Adults with Overweight or Obesity. New England Journal of Medicine, 2025, 393(11): 1077-1087. https://doi.org/10.1056/NEJMoa2500969
- Wilding JPH, Batterham RL, Calanna S et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. New England Journal of Medicine, 2021, 384(11): 989-1002. https://doi.org/10.1056/NEJMoa2032183
- Overgaard RV, Navarria A, Ingwersen SH et al. Clinical Pharmacokinetics of Oral Semaglutide: Analyses of Data from Clinical Pharmacology Trials. Clinical Pharmacokinetics, 2021, 60(10): 1335-1348. https://doi.org/10.1007/s40262-021-01025-x
- Overgaard RV, Birkhan O, Rathor N et al. Efficacy, Safety and PK of Once-Daily Oral Semaglutide 25 mg for Obesity With and Without Type 2 Diabetes in Comparison With Subcutaneous Semaglutide 2.4 mg. Diabetes, Obesity and Metabolism, 2026, 28(7): 5982-5991. https://doi.org/10.1111/dom.70769
- La Vignera S, Condorelli RA. Oral vs. Subcutaneous Semaglutide for Obesity Treatment: A Systematic Review of Efficacy, Safety, and Patient-Oriented Outcomes. Pharmaceuticals, 2026, 19(8): 1236. https://doi.org/10.3390/ph19081236
- Aroda VR, Aberle J, Bardtrum L et al. Efficacy and safety of once-daily oral semaglutide 25 mg and 50 mg compared with 14 mg in adults with type 2 diabetes (PIONEER PLUS). The Lancet, 2023, 402(10403): 693-704. https://doi.org/10.1016/S0140-6736(23)01127-3
- Pratley R, Amod A, Hoff ST et al. Oral semaglutide versus subcutaneous liraglutide and placebo in type 2 diabetes (PIONEER 4). The Lancet, 2019, 394(10192): 39-50. https://doi.org/10.1016/S0140-6736(19)31271-1