Dose equivalence between different incretin analogues is a weak concept. The molecules differ in structure, half-life, receptor selectivity, and in what has been studied clinically. One mg of semaglutide is not equivalent to one mg of something else in any meaningful sense. I have separated what I observed from what…
What steady state means for the decision to escalate — that is the question, and I have not found it answered plainly anywhere I have looked.
A question about steady state that I think has a definite answer, unlike most of what I ask here.
I have the reasoning below and I am fairly confident about the direction. I am not confident about the size, and the size is what the decision turns on.
Answering the question the opening post raises rather than the one it answers.
Worth separating steady state as a question about the compound from steady state as a question about the documentation. They get answered by different people and only one of them is answerable here.
I would put moderate confidence on the mainstream reading of steady state and no more. That is not scepticism for its own sake; it is where the sourcing actually stops.
Dose equivalence between different incretin analogues is a weak concept. The molecules differ in structure, half-life, receptor selectivity, and in what has been studied clinically. One mg of semaglutide is not equivalent to one mg of something else in any meaningful sense.
I have separated what I observed from what I concluded, which does not always happen.
Post #6 is the version of this I will quote in future. One addition.
Titrating on tolerability rather than on the calendar: some people escalate when they tolerate a dose well, others escalate on the prescribed schedule regardless. The published trials used a calendar-based schedule. Tolerability-based escalation has no formal evidence base but is not uncommon in practice.
Where I part company with post #6, and it is a narrow parting.
The question underneath steady state is usually "how would I tell?" rather than "what is true?", and that one has a method attached to it.
Write down what you would expect to see under each hypothesis before you collect anything. If they predict the same observation, collecting it will not help.
My experience of steady state contradicts the reply above. I am posting it as a data point rather than as a refutation, because one person's experience is exactly that.
Concentration and dose get conflated constantly in this subcategory. Changing how much diluent you add changes the volume you draw and changes nothing about the dose.
That matches what I was told, which is not the same as knowing it.
Steady state means the plasma concentration is stable from dose to dose. That happens around 4 to 5 half-lives. Before that, the concentration is rising with each dose. Escalating before steady state means escalating on incomplete information about the dose you are on.
The uncertainty is in the assumption, not in the calculation.
Post #9 is right about the mechanism and I think understates the practical bit.
Two things can be true about steady state at once: the mechanism is plausible and the evidence for the size of the effect is thin. Most of the argument here is people defending the first against attacks on the second.
The confident answers on steady state and the well-sourced answers are not the same answers, which is the most useful thing I have learned reading this category.
Concentration and dose get conflated constantly in this subcategory. Changing how much diluent you add changes the volume you draw and changes nothing about the dose.
A partial answer, offered because a partial answer beats none.
The four-week escalation interval is a convention from the pivotal trials, not a pharmacological constant. The pharmacological argument is that with a week-long half-life, four weeks approaches steady state and you can assess the dose fairly. That is an argument for not going faster. It is not an argument against going slower.
That is a cleaner way of putting what I was circling around.
Post #13 and I disagree about the size of the effect, not about the direction.
There is no published evidence about slower escalation because nobody studied it. That means the trials support not going faster and are silent on going slower, which is a different claim from "slower is fine".
Everything in post #17 holds. The case it does not cover is the one I have.
A request rather than an answer: could whoever has the primary source for steady state post it? I have seen the claim three times this month and each version had lost a qualifier.
The arithmetic of an intermediate dose: if the label says 1.0 mg and 2.0 mg, a dose strictly between them is off-label by definition. Some people compute it anyway. The reasoning is pharmacological — e.g., "I will split the difference between steps" — but it is reasoning from theory, not from evidence.
That is the shape of it. The detail is where I would expect to be corrected.
Post #20 describes the usual case. This is about the unusual one.
The honest answer on steady state is that it depends, and the useful part is the list of what it depends on. Four items, in rough order of how much they matter.
Most people get the first two right and then argue about the fourth.
I read the earlier replies on steady state twice before writing this, because I had assumed the opposite and wanted to be sure I was disagreeing with what was said rather than what I expected.
Concentration and dose get conflated constantly in this subcategory. Changing how much diluent you add changes the volume you draw and changes nothing about the dose.
Not a conclusion. A place to stand while looking for one.
A note on how steady state gets discussed rather than on steady state itself: the confident posts get the replies and the careful ones get ignored, and the careful ones have been right more often.
Useful. I have added it to my own notes with the date on it.
Taking post #26 at face value and following it one step further.
The four-week escalation interval is a convention from the pivotal trials, not a pharmacological constant. The pharmacological argument is that with a week-long half-life, four weeks approaches steady state and you can assess the dose fairly. That is an argument for not going faster. It is not an argument against going slower.
Post #29 and I disagree about the size of the effect, not about the direction.
Titrating on tolerability rather than on the calendar: some people escalate when they tolerate a dose well, others escalate on the prescribed schedule regardless. The published trials used a calendar-based schedule. Tolerability-based escalation has no formal evidence base but is not uncommon in practice.
Two people can read the same figure differently here and both be reasonable.