Guide to Prescription Writing in OPD

What is a Prescription?

Part 1 - Rational Prescribing: The 7 Steps

Step 1 - Make a Specific Diagnosis

Example: "Probable rheumatoid arthritis with active synovitis" - not just "joint pain."

Step 2 - Consider the Pathophysiologic Implications

Step 3 - Select a Specific Therapeutic Objective

• Relief of pain by reducing inflammation (short-term goal in RA)
• Arresting disease progression (long-term goal - may require different drugs)

Step 4 - Select the Drug of Choice

Example: In RA, if the patient has no ulcer disease, ibuprofen may be chosen. If they have prior GI bleeding, a COX-2 inhibitor or misoprostol co-prescription would be more appropriate.

Step 5 - Determine the Appropriate Dosing Regimen

• Assess organ function (renal, hepatic) needed for drug elimination
• Adjust dose in organ impairment
• Use the half-life to determine frequency

Example: Ibuprofen half-life ~2 hours → three to four times daily dosing required. Dose: 400-800 mg four times daily.

Step 6 - Monitor the Drug's Action and Plan an Endpoint

• Define what will be monitored (symptoms, labs, vitals)
• Tell the patient what side effects or warning signs to report immediately
• Specify duration of therapy (e.g., 7 days of antibiotics - patient should complete the course)
• For long-term conditions, explain refill requirements and how to obtain them
• State clearly what changes in condition require a change in therapy

Step 7 - Plan Patient Education

• Repeat and reinforce information at every visit
• The more toxic the drug, the more intensive the education needed
• Do not assume the pharmacist will do this - it is the prescriber's responsibility
• Involve the patient in each of the above steps (improves adherence, prevents errors with teratogenic drugs, etc.)

Part 2 - Elements of the OPD Prescription

Prescriber Identification (Elements 1-4)

Date (Element 5)

• Must appear near the top of the form
• Prescription has legal significance - a pharmacist should refuse to fill a prescription that is too old without telephone verification

Patient Information (Elements 6-7)

The Rx Body (Elements 8-11)

• Write in plain language or accepted abbreviations
• Specify route of administration
• Include timing relative to food if relevant
• Include any special instructions (e.g., "swallow whole," "do not crush")

Refill Instructions (Element 12)

• State number of refills permitted (e.g., "Refill x 3" or "Refill until [date]")
• Controlled substances have strict refill limitations by law

Childproof Container (Element 13)

• Default is childproof packaging
• Prescriber can waive this (check box or notation)
• Useful for elderly or arthritic patients who have difficulty opening safety caps

Prescriber Signature and DEA Number (Elements 14-17)

Part 3 - Common Prescribing Errors to Avoid

Part 4 - Special Considerations in OPD Prescribing

Generic vs. Brand Name

• Generic prescribing is preferred - lowers cost for the patient
• If a specific brand is required, write "Dispense as Written (DAW)" or "No Substitution"
• Some drugs (narrow therapeutic index like warfarin, lithium, certain antiepileptics) may warrant brand-specific dispensing

Controlled Substances

• Require DEA registration number
• Schedule II drugs (e.g., opioids, stimulants) cannot be refilled - a new prescription is needed each time
• Some states require triplicate or tamper-resistant prescription pads
• Electronic prescribing for controlled substances (EPCS) is now allowed in many jurisdictions

Electronic Prescribing (e-Prescribing)

• Reduces transcription errors
• Allows direct transmission to pharmacy
• Drug-drug interaction alerts built into most systems
• Required for controlled substances in some states
• Requires the same legal elements as a paper prescription

Pediatric Patients

• Always calculate dose by weight (mg/kg)
• Specify age and weight on the prescription
• Choose age-appropriate formulation (liquid vs. tablet)

Elderly Patients

• Start low, go slow
• Beware polypharmacy and drug-drug interactions
• Consider renal and hepatic function for dose adjustment
• Avoid Beers Criteria drugs when alternatives exist

Pregnant/Lactating Patients

• Confirm safety category for the drug
• Minimize drug use, especially in first trimester
• Document the risk-benefit discussion in the chart

Part 5 - A Sample OPD Prescription (Annotated)

Dr. Asha Mehta, MBBS, MD (Medicine)
City Health Clinic, 45 Main Road, Pune - 411001
Tel: 020-XXXXXXXX

Date: 12 July 2026

Patient Name: Mr. Ram Sharma          Age/Sex: 45 Y / M
Address: 22 Park Street, Pune

Rx
1. Tab. Ibuprofen 400 mg        [drug name + strength]
   Disp: 30 tablets              [quantity]
   Sig: 1 tab PO TID x 10 days with food   [instructions + duration]

2. Tab. Omeprazole 20 mg        [gastroprotection co-prescription]
   Disp: 10 capsules
   Sig: 1 cap PO OD before breakfast x 10 days

Refills: 0
No childproof container: [ ]

Diagnosis: Acute musculoskeletal pain (right knee)

Dr. Asha Mehta                  Reg. No. MH/XXXX/2015
Signature: _______________

Part 6 - WHO 6-Step Prescribing Model (Quick Reference)

1. Define the patient's problem
2. Specify the therapeutic objective
3. Verify the suitability of your chosen drug (efficacy, safety, cost, convenience)
4. Write the prescription with all required elements
5. Inform and instruct the patient
6. Monitor treatment and stop or modify if needed

Summary Checklist Before Signing Any OPD Prescription

• Correct patient name and details
• Today's date written
• Diagnosis or indication noted (or in the chart)
• Drug name (generic preferred), strength, formulation
• Dose, route, frequency, and duration all specified
• Quantity to dispense matches the intended course
• Refills stated or marked as zero
• Potential drug interactions checked
• Dose adjusted for renal/hepatic impairment if needed
• Patient counseled on how to take the drug and side effects to watch for
• Legible handwriting or e-prescription used
• Prescriber signature and registration number present
• DEA/license number added for controlled substances