One concrete data point for the thread. If you are going to change something, change one thing and give it long enough to express itself. Four weeks is the usual minimum for anything pharmacological on this board, and two weeks of data has told you almost nothing.

Worth separating that from thyroid monitoring, which this thread keeps folding into the same question. They behave differently and the advice does not transfer.

A narrower follow-up, since the general answer is now clear:

Why calcitonin screening is not recommended when the label carries a thyroid warning, because those two facts look contradictory from the outside?

TrialTracker_MD said:

If you are going to change something, change one thing and give it long enough to express itself.

Worth saying that the confident version of this is more useful to the person writing it than to the person reading it.

TrialTracker_MD said:

If you are going to change something, change one thing and give it long enough to express itself.

That is right for the common case. Whether it is right for the case being asked about depends on a detail that has not been given.

TrialTracker_MD said:

If you are going to change something, change one thing and give it long enough to express itself.

This answered a question I did not know how to ask. Printing the relevant bit and taking it with me.