PO (By Mouth / Oral)
A medical route abbreviation from Latin "per os," meaning that a medication or food must be administered orally by mouth.
💬 In Plain English
PO stands for "per os," which is Latin for "by mouth." When you see PO on your pet’s prescription label or discharge instructions, it simply means that the tablet, capsule, or liquid is meant to be swallowed orally. It distinguishes oral medications from topical drops for the skin, ears, or eyes, or injectable treatments given under the skin (SQ). Pills can often be given hidden inside a treat (like a Pill Pocket), coated in wet food, or gently administered directly into the back of the pet’s mouth.
🔬 Clinical & Technical Depth
For Vets & TechniciansFormal Clinical Definition
Pharmacological route abbreviation originating from Latin "per os" (by mouth). Directs gastrointestinal absorption following oral administration, subject to first-pass hepatic metabolism.
Why Veterinarians Use It
Veterinarians specify PO on prescription orders and patient charts to ensure clinic staff and owners administer medication through the oral route rather than into eyes, ears, or injections.
Clinical Context Encountered
Appears on virtually every oral prescription bottle dispensed from veterinary clinics (e.g., "Give 1 tablet PO BID").
Clinical Reference Guide (Prescription / Chart Abbreviation)
Administer the medication orally so that it is swallowed into the digestive tract.
Where You Encounter It
- Prescription bottles for chewable tablets, capsules, and oral syrups
- Hospital treatment records distinguishing oral from injectable drugs
- Discharge instructions for home care
- •In cats, dry-pilling (giving a dry tablet without water or food) can cause the pill to lodge in the esophagus, causing chemical burns, strictures, or ulcerations—always follow oral pills with 3–5 mL of water or a wet treat.
❓ Questions to Ask Your Veterinarian
Take these actionable questions with you to your next clinic visit or appointment:
- 1Can this pill be crushed or mixed into wet food, or must it be swallowed whole?
- 2Can I hide this medication inside a Pill Pocket, cheese, or peanut butter?
- 3Should this oral medication be followed by water or a meal to prevent it from sticking in the esophagus?
Academic & Clinical References
- Veterinary Medical Abbreviations and Prescription Notation StandardsOrganization: American Animal Hospital Association (AAHA) • Accessed: 2026-01-10https://www.aaha.org