The potential risks of over-the-counter (OTC) medications are often aggravated in vulnerable populations, such as older adults. The elevated patterns of older-adult OTC medication use do not necessarily translate into a greater understanding of these medications or their safety implications. The objective of this study was to assess how older adults’ knowledge, beliefs, and attitudes inform their decision-making regarding OTC use. Situational interviews were conducted in three community pharmacies with 87 older-adult participants to capture how they intended to use an OTC medication. The interviews were transcribed and qualitatively analyzed, generating seven key themes: (1) medication use concerns; (2) following label instructions; (3) wait time until medication effect; (4) responses to medication not working; (5) decision to stop medication; (6) sources of information; and (7) safety implications. This study shows substantial variations in older-adult OTC medication use while providing insight on factors that influence older adults’ appropriate OTC medication use and, in some cases, the potential for harmful effects.