Take at look at this document.
You’ll see there are some med school that will not accept any AP credits for physics. There are others that don’t formally require physics.
In general to be considered a strong applicant, students are encouraged to supplement any AP credits with at least an equal number of college credits in the same department.
If your son thinks he may want to apply to any of the med schools that won’t accept AP physics credits or will only partially accept them, then he needs to either retake algebra-based physics in college (and have the classes marked as a repeated class) or take a calculus based version of intro physics. Some colleges offer (or require) bio majors to take a non-engineering calc-based physics class. Check the course catalog at your son’s college for offerings.
Will NOT accept AP credit for physics:
Baylor, Cal Northstate, UC-Riverside, Kentucky, Tufts,
Requires an UL physics class to supplement any AP credits:
Loma Linda, Quinnipiac, Yale, Florida Atlantic, Central Florida, South Florida, Mercer, Loyola, Northwestern, Chicago, Indiana, Oakland-Beaumont, St Louis U, Nebraska, Nevada-Reno, Albany, Columbia, UNC-Chapel Hill, Oklahoma, South Carolina-Greenville, Tennessee,
Case by case consideration only:
Illinois, LSU-New Orleans, Boston, Dartmouth, North Dakota, NE Ohio , Ponce, South Dakota,
AP physics credits only partially fulfill admissions requirements:
Rochester, Harvard,