What pill has s489 on white side and 40mg on green side and is a capsule?

The pill with "s489" on one side and "40 mg" on the other side is identified as Diphenhydramine Hydrochloride 40 mg, which is an over-the-counter antihistamine commonly used for allergy relief, motion sickness, and as a sleep aid. It is typically found in capsule form and can cause drowsiness. Always consult a healthcare professional before taking any medication.