The case in front of me: nausea · ten · dulaglutide.
I have done this once and I suspect I got away with it rather than got it right.
For context: I keep records of every batch, every lot number and every result, so an answer that requires me to track something is fine.
What would you do, and what would you check afterwards?
Week 10 is day 70: on a four-week ladder that is week 2 of dose step 3, and — at the seven-day half-life this class runs on — 10 half-lives in. Steady state is about five half-lives, so day 35 is where the concentration stops climbing on its own. Day 70 is 5 weeks past it, which means the level is no longer the variable. That distinction is most of the question: at week 2 of a step, an effect that is still accumulating is indistinguishable from one that is not resolving unless you know which side of day 35 you are on. Nausea in this class tracks the rate of change more than the level: the trial programmes report it clustered in the fortnight after each step and decaying across the weeks that follow, which is why the week number is worth locating on the ladder before anything else. Dose decisions are made under supervision, and nothing here is medical advice.
In practice, the relevant anatomy is the area postrema, a circumventricular organ with an incomplete blood-brain barrier that functions as the chemoreceptor trigger zone.
Extending the interval before the next escalation is the intervention with the best evidence. Trials titrated at four-week intervals for exactly this reason.
| Event | Active arm | Placebo arm | Timing |
|---|---|---|---|
| Nausea | 40–45 % | 15–20 % | Peaks 1–2 wk after each step |
| Vomiting | 15–25 % | 5–8 % | Follows nausea |
| Diarrhoea | 20–30 % | 10–15 % | Early, variable |
| Constipation | 20–25 % | 8–12 % | Later onset, persistent |
| Discontinuation for GI events | 4–7 % | 1–2 % | Mostly during escalation |
Ranges span agents and doses; read the specific prescribing information for a specific figure.
Delayed gastric emptying contributes peripherally: a stomach that empties slowly stays full longer, and fullness plus a sensitised trigger zone is the combination that produces the characteristic symptom.
Area postrema involvement in nausea from GLP-1 receptor agonism is supported by lesion studies in animals and by the anatomy of the circumventricular organs.
Nothing here is medical advice; I am describing a pattern, not managing anybody.
Persistent vomiting is a clinical matter, not a tolerance matter.
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Browse resultsThis is the most common adverse effect in the class and the one with the most consistent management advice.
Tolerance develops through receptor desensitisation over one to two weeks at a stable dose. Escalating before that has happened resets the process, which is the mechanism behind most miserable titrations.
In practice, trial incidence for nausea in this class runs to roughly a quarter to a half of participants depending on agent and dose, concentrated in the escalation phase, with discontinuation for it in low single-figure percentages.
Severe abdominal pain radiating to the back is not ordinary nausea and needs urgent assessment.
Hold the dose rather than escalating. Tolerance needs one to two weeks to develop.
Ask PeptideStack is a static archive. Posting is closed, but the norms are worth stating: answer the question that was asked, show your working, cite the trial or the certificate, and say plainly where the evidence runs out.