A prescription is a set of instructions written quickly, in shorthand, by someone who reads and writes them all day. For the person receiving it, that shorthand can be genuinely opaque — and a misread instruction is one of the more avoidable causes of a medicine not working.
Why this matters
A large share of medicine-related problems come from a dose taken at the wrong time, a course stopped early, or two products taken together that should not be. Almost all of that is preventable by understanding the paper in your hand and asking about anything unclear before you leave.
What medical guidance says
The parts of a prescription
- Prescriber details — the doctor’s name, qualification and registration number, and the clinic or hospital.
- Patient details — name, age and often weight. Age and weight matter particularly for children, where doses are calculated from them.
- Date — which determines how long the prescription remains current.
- The medicines — each with its name, strength, dosage form, how much to take, how often, by which route, and for how long.
- Additional instructions — before or after food, avoid with certain foods, and similar notes.
- The prescriber’s signature.
Common abbreviations
Much of the shorthand descends from Latin. The ones you are most likely to see:
- OD — once daily. BD or BID — twice daily. TDS or TID — three times daily. QID — four times daily.
- SOS or PRN — only when needed, rather than on a fixed schedule.
- HS — at bedtime. OM — in the morning. ON — at night.
- AC — before food. PC — after food.
- PO — by mouth. IM — intramuscular injection. IV — intravenous. SC — subcutaneous.
- Stat — immediately, as a single dose now.
- x 5 days — the duration of the course.
- 1-0-1 — a common Indian notation for morning, afternoon and night. This example means one dose in the morning, none in the afternoon, one at night.
If any abbreviation on your prescription is not on this list, or the handwriting is unclear, ask. A pharmacist would far rather confirm than guess, and guessing is not acceptable practice.
Generic and brand names
Most medicines have two names: the generic name, which is the active ingredient, and one or more brand names under which companies sell it. Your prescription may carry either. Reading the generic name on the pack is what lets you recognise that two differently branded boxes contain the same ingredient — which is how accidental double dosing happens, particularly with common painkillers and cold preparations.
Before leaving the pharmacy, check that the name, strength and quantity on the pack match what is written on your prescription. It takes a few seconds and catches most dispensing confusions.
Questions worth asking
- What is this medicine for? Knowing the purpose makes the course much easier to complete.
- How exactly do I take it, and does the timing relate to food?
- For how many days, and what should I do if I miss a dose?
- What side effects are common, and which ones should prompt me to call you?
- Does it interact with anything else I take, including supplements and anything bought without a prescription?
- Should I avoid alcohol, driving, or any particular food while taking it?
- Do I need a follow-up appointment or a repeat test?
Keep your prescriptions rather than discarding them. A record of what you have been prescribed, and when, is genuinely useful at your next appointment and in an emergency.
Related reading: Medicine expiry dates: what they actually mean
When to consult a doctor
Contact your doctor or pharmacist before starting the medicine if any part of the prescription is illegible or ambiguous, if the dispensed pack does not match what was written, if you are already taking something similar, or if you are pregnant, breastfeeding or have a known allergy that may not have been noted.
Never take a prescription written for someone else, and never share yours. Seek urgent medical care for signs of a severe allergic reaction — swelling of the face, lips or tongue, difficulty breathing, or a widespread rash after a dose.
Frequently asked questions
- What does 1-0-1 mean on my prescription?
- It is a common Indian shorthand for morning, afternoon and night in that order. 1-0-1 means one dose in the morning, none in the afternoon and one at night. 1-1-1 would mean one dose at each of the three times.
- Is a generic medicine the same as the branded one?
- A generic contains the same active ingredient at the same strength and dosage form. Brand names differ because different companies market the same ingredient. If you have any question about a substitution, ask your pharmacist or the doctor who prescribed it.
- What should I do if I miss a dose?
- The right action varies by medicine, so ask your doctor or pharmacist for that specific product. As a general principle, do not take a double dose to compensate unless you have been explicitly told to.
- Can I stop once I feel better?
- Not without asking. With antibiotics in particular, stopping early can leave an infection incompletely treated and contributes to resistance. Many long-term medicines also should not be stopped abruptly. Ask the doctor who prescribed it.
- The handwriting is unclear. What should I do?
- Ask the pharmacist to confirm it, and where there is any doubt they should check with the prescriber. Never guess, and never take a medicine you are not certain about.
References
- Medication Without Harm — global patient safety challenge — World Health Organization (WHO)
- Guidelines on prescription writing and rational use of medicines — Ministry of Health & Family Welfare, Government of India
- National List of Essential Medicines — Ministry of Health & Family Welfare, Government of India