Most patients collect their prescription, hand it to a pharmacist and trust that whatever comes back is correct. That works most of the time. But prescriptions contain errors — studies suggest three to eight percent contain at least one mistake — and patients who understand what they're looking at are far better placed to catch them.
Here's every field on a standard prescription, explained.
Prescriber information
The top of a prescription identifies who wrote it: name, qualifications, practice address and contact number. This matters because it establishes who is responsible for the prescription and allows verification. If you're filling a prescription from a specialist you've never seen before, confirming this information is worth a quick check.
Patient details
Name, date of birth and sometimes address. The pharmacist uses this to confirm they're dispensing to the right person. If any of these are wrong — a misspelt name, a transposed date of birth — ask for a correction before leaving the clinic. A mismatch can cause delays at the pharmacy or create complications with insurance claims.
Drug name: generic vs brand
Prescriptions may use a drug's generic name (the scientific name of the active ingredient), a brand name (the manufacturer's marketing name), or both. Generic and brand versions of the same drug contain identical active ingredients at identical doses — the difference is price and, in some cases, inactive ingredients that affect tolerability.
If a prescription specifies brand only, ask whether a generic substitute is available. If it specifies generic, the pharmacist will typically dispense whatever generic is in stock.
Dose and strength
The dose is the amount of the drug per administration (e.g., 500 mg, 20 mg). The strength is usually the same thing expressed as the concentration in the tablet or liquid. Confirm that the strength you've been prescribed matches what's in the box. If you've previously taken a different strength of the same medication, check with your pharmacist before assuming the instructions are the same.
Frequency abbreviations
Prescriptions routinely use Latin abbreviations for frequency. The most common ones:
- OD / QD — once daily
- BD / BID — twice daily
- TDS / TID — three times daily
- QDS / QID — four times daily
- PRN — as needed (when required)
- AC — before meals
- PC — after meals
- HS — at bedtime
- STAT — immediately
Quantity and repeats
The quantity tells you how many tablets, millilitres or patches have been prescribed. Repeats (or refills) tell you how many times the prescription can be dispensed without a new consultation. A prescription marked '0 repeats' means you'll need to see your prescriber again before getting more — pay attention to this for ongoing medications.
Special instructions
Instructions like 'take with food', 'avoid direct sunlight', 'do not crush or chew', or 'do not take with grapefruit juice' are clinically meaningful — they affect how the drug is absorbed or what side effects you might experience. These aren't pharmacist suggestions; they're clinical instructions that change the medication's safety profile.
Before you leave the pharmacy
Confirm drug name, strength, dose, frequency and quantity match the original prescription. Ask if anything looks unfamiliar. If you're collecting a medication you take regularly and the tablet looks different — different colour, shape or size — ask the pharmacist to confirm it's the same drug and dose before taking it.