2.1 Prescription Intake and Interpretation

Quick Answer: A valid prescription requires patient name, drug name/strength/quantity, directions (sig), prescriber info with DEA number for controls, and date written. Pharmacy technicians must verify all elements and understand sig codes to process prescriptions accurately.

Elements of a Valid Prescription

Every prescription must contain these essential elements:

Common Sig Codes and Abbreviations

Sig codes are Latin-based abbreviations that describe how medications should be taken:

Frequency Abbreviations

Route Abbreviations

Dosage Form Abbreviations

Example Sig Interpretation

Rx: Lisinopril 10mg #30 Sig: i tab PO QD

Translation: Take one (i) tablet by mouth (PO) once daily (QD)

Rx: Amoxicillin 500mg #21 Sig: i cap PO TID x 7 days

Translation: Take one (i) capsule by mouth (PO) three times daily (TID) for 7 days

DAW (Dispense As Written) Codes

DAW codes indicate whether generic substitution is allowed:

Exam Tip: DAW-0 means the pharmacist CAN substitute with a generic. DAW-1 means the prescriber requires brand only. DAW-2 means the patient requested brand name.

Prescription Verification Steps

1. Verify patient identity - Confirm name, DOB, address, allergies
2. Check prescription validity - Date, completeness, authenticity
3. Verify prescriber authority - Licensed, DEA valid for controls
4. Screen for interactions - Drug-drug, drug-disease, allergies
5. Confirm insurance coverage - Prior authorization if needed
6. Perform DUR - Drug utilization review
7. Have pharmacist verify - Final check before dispensing

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Required Components of a Valid Prescription

Before entering any prescription, the technician confirms it is complete. A missing element must be obtained from the prescriber, not guessed.

Exam Tip: A controlled-substance prescription additionally requires the prescriber's DEA number and, for Schedule II, cannot be refilled. If any required element is missing, the technician contacts the prescriber's office to complete it.

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Common SIG Codes You Must Know

SIG codes are Latin abbreviations the prescriber uses to direct administration. The technician translates them into clear English on the label.

Exam Trap: The ISMP error-prone list discourages "QD", "QOD", and "U". Expect a question asking you to recognize these as dangerous abbreviations that should be written out.

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Prescription Origins and DAW Decision Logic

Prescriptions arrive written, by telephone/verbal (taken by the pharmacist), by fax, or electronically (e-prescribing). The technician inputs and processes each origin but cannot accept a new verbal controlled-substance order in most states.

When choosing whether to substitute a generic, the technician reads the DAW code: DAW-0 allows substitution, while DAW-1 (prescriber) and DAW-2 (patient) block it. Selecting the wrong DAW code can cause a claim rejection or an incorrect copay, so accuracy here directly affects adjudication.

Worked Example: A prescription reads "Amoxicillin 500 mg, i cap PO TID x 10 days, DAW-0." Translation for the label: "Take one capsule by mouth three times daily for 10 days." Because DAW-0 is set, the pharmacist may dispense an A-rated generic.