Eloralintide's two main side effects behave differently from each other, and neither follows the simple rule that more drug means more trouble. Nausea ranged from 11% to 64% across the trial arms and appears driven by the starting dose. Fatigue reached 46% and tracks the final dose. Understanding which is which changes how the drug would be taken.
Every arm, both reactions
From the 48-week phase 2 trial, 263 adults across seven arms. These are the two adverse events the published report quantifies.
| Arm | Weight loss | Nausea | Fatigue |
|---|---|---|---|
| Placebo | −0.4% | 14% | 12% |
| 1 mg | −9% | 11% | 0% |
| 3 mg | −12% | 13% | 13% |
| 3 → 9 mg | −16% | 25% | 21% |
| 6 mg | −18% | 64% | 29% |
| 6 → 9 mg | −20% | 54% | 46% |
| 9 mg | −20% | 33% | 43% |
Two things in that table do not fit a dose-response curve, and they do not fit it in different directions.
Nausea: the starting dose, not the dose
The 6 mg arm reported nausea in 64% of patients. The 9 mg arm — half again as much drug, and more weight loss — reported 33%. A higher dose producing half the nausea cannot be explained by the dose.
What separates them is the entry point. Rank the arms by how gently they began:
- Started at 1 mg → 11% nausea
- Started at 3 mg → 13%, and 25% for the arm that went on to 9 mg
- Started at 6 mg → 64% staying there, 54% going on to 9 mg
- Started at 9 mg → 33%
The 9 mg arm is the untidy one and it should be said rather than smoothed over — if starting dose were the whole story it would be the worst arm, not the middle. The trial was designed to compare regimens, not to isolate this effect, so what the table supports is a strong pattern with one exception rather than a clean law.
The practical reading: beginning at 6 mg looks like the worst available choice. It produced less weight loss than 9 mg and roughly double the nausea. The arm that climbed from 3 mg reached 16% weight loss with 25% nausea — four fifths of the maximum effect at about a third of the discomfort.
Fatigue: the final dose, and higher than you would expect
Fatigue does the opposite. It rises with where the arm ended: 0% at 1 mg, 13% at 3 mg, 29% at 6 mg, and 43% to 46% in the arms finishing at 9 mg. Escalation makes no difference — the 6→9 mg arm reported 46%, slightly more than the fixed 9 mg arm's 43%.
That number deserves attention. Fatigue in 43 to 46% of patients is higher than the GLP-1 drugs report: Wegovy's label lists 11% and Foundayo's 9%. Nearly half the participants on the top eloralintide doses reported it, against 12% on placebo.
Because it behaves differently from nausea, it is probably a different mechanism — and unlike nausea, there is no evidence here that a gentler start avoids it. If this holds in phase 3, fatigue rather than nausea may be the reaction that decides whether people stay on this drug.
What is not in the published data
The report quantifies nausea and fatigue. It does not give figures for the other things a reader would want:
- Vomiting, diarrhoea, constipation — standard rows in any approved label, absent here.
- Discontinuation rates for adverse events. This is the number that best captures tolerability, and it is the one we do not have.
- Severity breakdowns. How much of the 64% was mild is not stated.
- Serious adverse events. Not enumerated in the published summary.
This is what a phase 2 publication looks like compared with a label. For approved drugs we can print thirteen reactions across four dose columns; for eloralintide there are two reactions and no discontinuation figure. The gap is the difference between a trial report and a regulatory filing, and it will close if the drug is approved.
How this compares with the drugs you can get
| Drug | Nausea | Fatigue |
|---|---|---|
| Wegovy 2.4 mg | 44% | 11% |
| Foundayo 17.2 mg | 35% | 9% |
| Eloralintide 9 mg | 33% | 43% |
| Zepbound 15 mg | 28% | 7% |
| Eloralintide 6 mg (fixed) | 64% | 29% |
On nausea at the top dose, eloralintide sits mid-table — better than Wegovy, worse than Zepbound. On fatigue it is four times any of them.
These are separate trials with different reporting standards, so the comparison is directional. But it points at something real: an amylin drug is not simply a GLP-1 with a different name on it. Different pathway, different profile, different trade.
What this means if it is approved
Two things follow from the table, if the pattern holds in phase 3.
The escalation schedule will matter more than usual. Most GLP-1 drugs titrate to reduce gastrointestinal effects; here the data suggests the starting dose specifically, rather than the pace overall, is what determines them.
And fatigue will need managing in a way it does not for the current drugs. At 43% it is not a footnote.
Neither can be acted on yet. Eloralintide is not approved and cannot be prescribed — the trial data, the mechanism and where the programme stands are in the eloralintide overview, and the full efficacy picture in eloralintide weight loss.
The rest of the set
What is eloralintide, eloralintide weight loss, and how the profile compares with the drugs you can get: vs Wegovy and vs Ozempic.
Scientific References
3 sources- 1
Billings LK, Hsia S, Bays H, et al.
Eloralintide, a selective amylin receptor agonist for the treatment of obesity: a 48-week phase 2, multicentre, double-blind, randomised, placebo-controlled trial
The Lancet · 406(10520) · 2025PMID: 41207310
- 2
Novo Nordisk
WEGOVY (semaglutide) — Prescribing Information, §6.1 Table 3
DailyMed, U.S. National Library of Medicine · 2026
NIH - 3
Eli Lilly and Company
ZEPBOUND (tirzepatide) — Prescribing Information, §6.1
DailyMed, U.S. National Library of Medicine · 2026
NIH
References open in a new tab. Content is reviewed against peer-reviewed literature as part of our editorial policy.
About the author
Editor, Modern Weight Science
Claudiu Gheorghe is the editor of Modern Weight Science. He is not a physician. His role is to synthesize peer-reviewed studies, clinical-trial data, and FDA prescribing information into clear, plain-language explanations, and to make sure every factual claim on the site traces back to a cited source. Any decision about starting, changing, or stopping a medication belongs with a licensed clinician who knows your history.
Every claim is checked against peer-reviewed research through our review process and fact-checking policy.
Frequently Asked Questions
What are the side effects of eloralintide?
The published phase 2 quantifies two: nausea and fatigue. Nausea ranged from 11% to 64% depending on the trial arm, and fatigue from 0% to 46%, against 14% and 12% on placebo. No figures for vomiting, diarrhoea, constipation or discontinuation have been published, because a phase 2 trial report is not a regulatory label.
Why did a lower eloralintide dose cause more nausea?
Because the arms started differently. The fixed 6 mg arm reported 64% nausea while the 9 mg arm reported 33%, and a higher dose cannot be inherently gentler. The arms with the least nausea began at 1 mg and 3 mg; those with the most began at 6 mg. The pattern points at the starting dose, with the 9 mg arm as an untidy exception the trial was not designed to explain.
Does eloralintide cause fatigue?
Yes, and more than the approved drugs do. Fatigue was reported by 43% of patients on 9 mg and 46% on the arm escalating from 6 mg to 9 mg, against 12% on placebo. For comparison, Wegovy's label lists 11% and Foundayo's 9%. Unlike the nausea, fatigue tracked the final dose, so a gentler start does not appear to avoid it.
Is eloralintide better tolerated than Wegovy?
On nausea at the top dose, yes: 33% against Wegovy's 44%. On fatigue, clearly not: 43% against 11%. These come from separate trials with different reporting standards, so read the direction rather than the decimals — but the picture is of a different profile rather than a better one. An amylin drug is not a GLP-1 with a new name.
How many people stopped taking eloralintide because of side effects?
That figure has not been published. Discontinuation for adverse events is the single most useful tolerability number and the phase 2 report does not give it. It is one of several things — alongside vomiting, diarrhoea and severity breakdowns — that would appear in a label and does not appear in a trial publication.
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Where to read next
Not medical advice. This guide is for general education only. GLP-1 medications, dosing, and treatment suitability are decisions for you and a licensed clinician who knows your full medical history.