Topic summary

Substitution between formats during a shortage

Access › Shortages compounding FDA formulary shortage Solved Closed

This is a generated summary. It shows the 9 most-liked posts from a topic of 124, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.

DSakamotoTL3Regular Solution27 May 2025#3

t.brandt, post #2: A request rather than an answer: could whoever has the primary source for substitution between formats post it? I have seen the claim three times this month and each version had lost a qualifier. Go to post

Source for the substitution between formats figure, since it was asked for. It is in the discussion rather than the abstract, which is why the version circulating is stronger than the paper is.

Reading the surrounding paragraph is worth the two minutes. The authors are more careful than their summarisers.

29 likes in reply to #2 14mo

integrator_traceTL2Member2 Jul 2025#17

t.marchetti, post #14: This follows post #11 rather than contradicting it. Regional differences during a shortage are large, and a supply position in one country says nothing about another. Go to post

That is consistent with mine, for whatever one more account is worth.

28 likes in reply to #14 13mo

d.yilmazTL231 Jul 2025#31

d.nilsen, post #27: Taking post #24 at face value and following it one step further. Where a shortage forces a gap, the pharmacokinetics mean a missed week is a perturbation rather than a reset, which is worth knowing. It is one reading of the data and not the only reasonable one. Go to post

The documentation on substitution between formats is better than this thread and I say that as someone who has posted in the thread.

32 likes in reply to #27 12mo

so.cardosoTL226 Aug 2025#45

a.westergaard, post #9: Switching presentation or strength during a shortage is a prescribing decision rather than a substitution anybody should improvise. Go to post

Picking up post #42: that is the part I would want checked first.

Manufacturer allocation decisions during a shortage are commercial and are rarely explained, which is frustrating and is not evidence of anything.

The short answer was in the first line; everything after is the working.

31 likes in reply to #9 11mo

f.kimaniTL25 Sep 2025#51

On post #47 — agreed on the reasoning, with one qualification.

Substitution between formats would be much easier to settle if anyone reported the denominator. Almost nobody reports the denominator.

29 likes 11mo

s.silvaTL230 Sep 2025#66

The reason substitution between formats is hard to answer is that the obvious measurement and the relevant quantity are not the same thing, and substituting one for the other is silent.

29 likes 10mo

f.fenwickTL3Regular14 Nov 2025#95

KForsberg, post #93: On post #91 — agreed on the reasoning, with one qualification. The published shortage register maintained by the national regulator is the authoritative source here, and it is updated far more often than any thread. I have no interest in any supplier named above. Go to post

Saving this. It is the version I will quote when the question comes round again.

27 likes in reply to #93 8mo

l.aaltonenTL3Regular20 Dec 2025#120

Where a shortage forces a gap, the pharmacokinetics mean a missed week is a perturbation rather than a reset, which is worth knowing.

27 likes 7mo

preregisteredTL3Research methods23 Dec 2025#122

z.yildiz, post #84: Managing an unplanned gap: if a shortage causes a gap in treatment, the questions are how long the gap will be and how that affects your condition. Discussing with your clinician is prudent if the gap is weeks or longer. That holds under the stated conditions and I have stated them. Go to post

Worth separating substitution between formats as a question about the compound from substitution between formats as a question about the documentation. They get answered by different people and only one of them is answerable here.

28 likes in reply to #84 7mo

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Substitution between formats during a shortage — what changed sinceAccess › Shortages · 21 replies

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