Fatigue on semaglutide — caloric deficit vs direct drug effect

Dr.NateNeph said:

The mechanism that matters here is not stomach emptying, it is central.

Pushing back on Dr.NateNeph here. The trial means are being read too generously in this thread. STEP populations were selected, supported, and titrated by protocol, and the real-world curves are consistently a few points worse. That difference is not noise, it is what happens when you remove the study infrastructure.

The figures, for anyone assembling their own picture. Worth knowing that the injection site changes very little. Abdomen, thigh and upper arm are bioequivalent for semaglutide, so a site change is not a plausible explanation for a bad week.

RetaRick_CA said:

The trial means are being read too generously in this thread.

Adding the part of the answer the thread has not reached. Mostly the deficit, and the useful part of that answer is that it is testable. Fatigue driven by a deficit tracks intake, improves within a day or two of eating properly, and worsens on the days you eat least. Fatigue that is flat regardless of intake, or that arrives on a fixed day after dosing, is behaving like a drug effect. Before assuming either, rule out the boring causes — iron, B12, thyroid, and sleep — because a fast deficit unmasks deficiencies that were previously subclinical.

Following on from jim_asheville — and this may be the naive question:

Whether the fatigue is a direct drug effect or simply the caloric deficit, because the answer changes what you do about it?

OP back with an update, since a thread like this is useless without one.

Following this thread I went back and re-read the extension data properly. The point about trough rather than peak explains the pattern I was seeing on day six, which I had been blaming on the vial.