On cagrilintide dosing, two things exist: a documented trial titration protocol, and a widely circulated community practice with no clinical validation whatsoever.
Neither is a guideline. No body has published a cagrilintide dosing guideline. Here is what is known and what is not.
[What trials used]
The Phase II monotherapy trial tested 0.3, 0.6, 1.2, 2.4 and 4.5 mg once weekly, titrating to target over up to six weeks (Lau et al., 2021, PMID 34798060).
The Phase Ib combination study escalated cagrilintide and semaglutide at four-week intervals to target dose (Enebo et al., 2021, PMID 33894838).
Phase III settled on 2.4 mg of each drug. The newest trials are testing a lower 1 mg / 1 mg regimen.
One key detail: 4.5 mg was dropped after Phase II. It produced more weight loss than 2.4 mg but higher nausea rates, and Novo Nordisk did not pursue it.
[What the community circulates]
Grey-market cagrilintide comes in two forms: standalone vials, usually 5 mg or 10 mg; or premixed with retatrutide, most commonly 12.5 mg retatrutide plus 2.5 mg cagrilintide.
The titration protocol circulating online starts cagrilintide at 0.25 mg weekly, then 0.5 mg, 1.0 mg, 1.7 mg, 2.4 mg.
That schedule comes from no cagrilintide trial. It is copied directly from semaglutide's label. Many protocols even suggest adding cagrilintide only two months into retatrutide treatment.
None of these protocols has been clinically validated, and no community efficacy dataset of any size exists.
[The maths problem with premixed vials]
A fixed ratio means one drug's dose dictates the other's.
Take a 5:1 premix:
- 4 mg retatrutide = 0.8 mg cagrilintide
- 8 mg retatrutide = 1.6 mg cagrilintide
- 12 mg retatrutide = 2.4 mg cagrilintide
To adjust cagrilintide alone, you must change the retatrutide dose too. In clinical trials, the two were titrated separately — precisely to find each one's optimal dose.
There is a second consequence: if nausea appears, you cannot tell which peptide caused it.
[Reconstitution maths for standalone vials]
For standalone cagrilintide, using a standard U-100 insulin syringe:
5 mg vial + 2 ml water (2.5 mg/ml):
- 0.25 mg = 0.10 ml (10 units)
- 0.5 mg = 0.20 ml (20 units)
- 1.0 mg = 0.40 ml (40 units)
- 1.7 mg = 0.68 ml (68 units)
- 2.4 mg = 0.96 ml (96 units)
10 mg vial + 2 ml water (5 mg/ml):
- 0.25 mg = 0.05 ml (5 units)
- 0.5 mg = 0.10 ml (10 units)
- 1.0 mg = 0.20 ml (20 units)
- 1.7 mg = 0.34 ml (34 units)
- 2.4 mg = 0.48 ml (48 units)
A 5 mg cagrilintide vial lasts only two doses at 2.4 mg weekly. That matters before comparing prices, because cagrilintide's per-mg cost at target dose is misleading.
[The caveat]
No verified cagrilintide protocol exists outside clinical trials. Trial protocols are facts about the trials, not operating instructions.
For the retatrutide combination, the dosing picture is even emptier: no human trial, no titration study, no safe-dose data.