Four Pills, Two Days

A trekker on a remote solo route must swallow exactly one tablet of drug A and one of drug B every day — a doubled dose of either, or a skipped one, is dangerous. The tablets look and feel completely identical. This morning she fumbles the bottles and ends up with three loose tablets in her palm: one A and two B, now hopelessly mixed. Exactly one A tablet remains in its bottle, and every tablet is precious. How does she take exactly one A and one B both today and tomorrow, wasting nothing?