GLP-1 receptor desensitization and tachyphylaxis — why plateaus happen

Dr.GastroMayo said:

Genuine plateaus happen too, and the mechanism is metabolic adaptation plus a smaller body.

Genuinely useful, thank you. I had the facts and not the framework. Adding it to my notes with a link back to this thread.

From the other side of the consultation, briefly.

Receptor pharmacology relevant to the pharmacology: semaglutide is a GLP-1R agonist with a C-18 fatty acid chain that enables albumin binding (>99%), creating a depot effect with a ~168-hour half-life enabling weekly dosing[1].

Tirzepatide is a dual GIP/GLP-1R agonist with higher GIP affinity (5:1 GIP:GLP-1 potency ratio). The GIP component may enhance beta-cell function and adipocyte lipid metabolism beyond what GLP-1 alone achieves.

For the pharmacology, the pharmacology explains the clinical differences between these agents.

MASHdoc_SA said:

Semaglutide structural biology relevant to the pharmacology: semaglutide is a 31-amino acid peptide with 94% homology to native GLP-1(7-36).

This is where I part company with the consensus forming above. The "it is your intake" reflex here gets tiring. Some people genuinely stop responding at a dose that worked, and telling them to track harder when they have already tracked is how people stop posting.

NeuroNate said:

The mechanism is more central than most summaries suggest.

Amycretin (AMY/GLP-1 dual agonist) emerging data relevant to the pharmacology: Phase 1 showed -13.1% body weight at only 12 weeks, the fastest trajectory ever seen for an anti-obesity agent[1].

Amylin receptor agonism enhances satiety signaling through the area postrema and reduces glucagon secretion. Combined with GLP-1R agonism, this dual mechanism may produce even greater efficacy than current agents.

Early-stage data — interpret with caution. But the trajectory is extraordinary.

Moderator note: leaving this open. It is being argued well and the disagreement is the useful part. Carry on.