ASA (drug caution code): Abbreviation on a medication that indicates it contains acetylsalicylic acid (aspirin).

This special caution code is intended to be a warning for patients with specific medical conditions. If you see it or another possible caution code on a prescription, talk to your pharmacist about it before using the medicine.

While not a part of the historical heritage of ancient prescription abbreviations, drug caution codes provide very valuable warnings.