As an extension of this M.Y. question,
Can one take medication on Shabbat on preparation for a procedure that occurs the next day or in a few days?
For example, can one take:
- amoxicillin for oral surgery to be done the following Tuesday
- "goop" for a colonoscopy done on Sunday
In both cases, the doctor has prescribed the medication.
The linked question seems to address preventing a medical condition that is likely to occur on the same day. In the examples that I mentioned, there is no condition or illness that will occur. The "goop" is not to prevent an illness. It is to aid a procedure. Amoxicillin is taken to reduce the possibility of infection after the oral surgery. It is not certain that one may become infected without taking it, but the doctor is being safe.