Oral contraceptives and delayed emptying: what the data shows — setting out what I have, and where I think it stops being reliable.
A follow-up question about Oral contraceptives and delayed emptying that I did not know to ask the first time.
The earlier thread answered what I asked. What I should have asked is below, and I think it is the one that matters.
Research-use-only compounds have no interaction data of any kind, because interaction studies are done on medicines being developed for use in people.
Post #3 is the version of this I will quote in future. One addition.
Food interactions: most interactions are absorption interactions. Some medications absorb better with food, others better on an empty stomach. With an incretin agonist that already slows gastric emptying, food effects interact with the drug effect as well.
Post #3 describes the usual case. This is about the unusual one.
Oral contraceptive absorption has been studied specifically for some compounds in this class and the findings are compound-specific. Generalising from one to another is not supported.
The number is defensible. The precision I gave it is not.
The practical advice most consistently given by pharmacists here is to keep the timing of other oral medication consistent rather than to change it, because consistency is what makes a problem visible.
The strength of my opinion here exceeds the strength of my evidence.
I think the Oral contraceptives and delayed emptying question is answerable and has not been answered, which is a more optimistic position than most of this thread.
Alcohol is not contraindicated in the labelling and it does irritate a stomach that is already emptying slowly. There is no published interaction study, and the conservative reading is the obvious one.
Thyroid medications: semaglutide is associated with a slowing of gastric emptying, which might affect thyroid medication absorption if they are taken very close together. Separating them by a few hours is the conservative approach.
Agreed on all of that, and I have nothing to add to it.
Fine by me. I had wanted a stronger conclusion and there is not one available.
Oral medications versus time: if you take an oral medication 30 minutes before semaglutide (which slows gastric emptying), the delayed stomach emptying affects when and where the oral medication is absorbed. Separating by a larger interval (1 to 2 hours) usually resolves this.
Second-hand, so weight it accordingly.
Where a published interaction study exists it usually reports an area-under-curve ratio, and that number is far more informative than a yes-or-no answer.
Posting it because the silence on this was starting to look like agreement.
Coming back to post #12, because the follow-up matters more than the original answer.
Oral contraceptives and delayed emptying is a good example of a question where the honest answer is boring and the interesting answers are unsupported. I would go with boring.
Delayed gastric emptying is the mechanism behind most of the plausible interactions in this class: anything whose absorption depends on how quickly the stomach empties can behave differently.
I have left out the parts I could not verify.
Post #16 answers the question as asked. The question underneath it is different.
On Oral contraceptives and delayed emptying, I would rather understate and be corrected upward than overstate and be quoted. That is a house style here and it is a good one.
I read post #14 twice before replying, because I had assumed the opposite.
Whatever the answer on Oral contraceptives and delayed emptying turns out to be, the method for getting there is the same: state the assumption, do the arithmetic in public, invite the correction.
The arithmetic in post #16 is right; the assumption feeding it is the part to check.
The practical advice most consistently given by pharmacists here is to keep the timing of other oral medication consistent rather than to change it, because consistency is what makes a problem visible.
This is where my knowledge stops and I would rather mark the edge than blur it.
Speaking only to Oral contraceptives and delayed emptying as I have actually seen it, rather than as it is usually described: the effect is real, it is smaller than the thread suggests, and the variance between people is larger than the effect.
Everything in post #19 holds. The case it does not cover is the one I have.
Research-use-only compounds have no interaction data of any kind, because interaction studies are done on medicines being developed for use in people.
On balance I think that is right, and I would not bet much on it.
Food interactions: most interactions are absorption interactions. Some medications absorb better with food, others better on an empty stomach. With an incretin agonist that already slows gastric emptying, food effects interact with the drug effect as well.
Alcohol is not contraindicated in the labelling and it does irritate a stomach that is already emptying slowly. There is no published interaction study, and the conservative reading is the obvious one.
Oral contraceptive absorption has been studied specifically for some compounds in this class and the findings are compound-specific. Generalising from one to another is not supported.
Where I part company with post #27, and it is a narrow parting.
Oral medications versus time: if you take an oral medication 30 minutes before semaglutide (which slows gastric emptying), the delayed stomach emptying affects when and where the oral medication is absorbed. Separating by a larger interval (1 to 2 hours) usually resolves this.
I have written this out at length because the short version keeps being misread.
Post #27 is the version of this I will quote in future. One addition.
I keep a log for Oral contraceptives and delayed emptying specifically because my memory of it turned out to be systematically wrong in one direction. Six weeks of notes cost nothing and settled it.