I cannot say this for all medications, simply because I did not study it in that detail. But the heading for this thread is correct – alcohol is a bad ingredient to add to any medication. Peruse package instructions for any medication, including those mentioned in the OP, and any others. Almost every one I have seen spells out that it should not be mixed with alcohol. That means, when taking it, don’t drink at all. Even if the combination is not lethal (and many are), the medication loses its effectiveness. I safely say that halacha exempts anyone on meds from drinking alcohol on Purim, as well as for Kiddush. Find me a posek that says differently.
This is a place to ask a simple question about Purim. The Gemora brings a halacha, which appears to be refuted in the context of the gemora, but was included in Shulchan Aruch, the famed חייב אינש לאבשומי בפוריא. In the Megillah itself, we find 4 mitzvos of Purim – Reading the Megillah, Matanos Lo’evyonim, MIshloach Manos, and Seudah. Nowhere is drinking as one of the mitzvos of the day mentioned in the Megillah. It seems apparent that it is an addition that is secondary to the other mitzvos, presumably Seudah. As such, it is not its own “mitzvah”, and the discussion about how to be machmir on this seems to be baseless.
In the context of the question I posed, the idea to be “machmir” to drink when there is danger involved, becomes quite the opposite.