Clinical Skills

Prescribing Safety

Master safe prescribing for medical finals and Foundation Year 1. Covers legal frameworks, drug calculations, common drug classes, and the SCRIPT prescribing assessment.

Legal Framework for Prescribing

  • Foundation doctors can prescribe as fully registered GMC doctors
  • Controlled drugs require specific prescription requirements (date, patient details, drug, dose, route, quantity in words and figures, prescriber signature)
  • Refer to the BNF for licensed indications, doses, interactions, and cautions
  • Medicines should only be prescribed within your competence

The SCRIPT Framework

SCRIPT (Systematic, Clinically Relevant, Individualised Prescription Tool) is used by many UK medical schools for prescribing assessments. Key principles:

  1. Patient details — name, DOB, hospital number, weight (for weight-based dosing)
  2. Allergies — documented with reaction type
  3. Drug — approved (generic) name, not brand name
  4. Dose — correct for age, weight, renal/hepatic function
  5. Route — oral, IV, IM, SC, topical, inhaled
  6. Frequency — OD, BD, TDS, QDS, PRN
  7. Duration — specify or mark as ongoing
  8. Indication — some forms require documentation
  9. Signature and date

Drug Calculations

Basic Formula

Volume required = (Dose required ÷ Stock concentration) × Volume of stock

Infusion Rates

Rate (mL/hr) = (Dose in mg/hr) ÷ (Concentration in mg/mL)

Weight-Based Dosing

Total dose = Dose per kg × Patient weight (kg)

High-Risk Medicines

The following require extra care and double-checking:

  • Anticoagulants — warfarin (INR monitoring), LMWH (renal dose adjustment), DOACs
  • Insulin — always prescribe in units, never abbreviate "U" to avoid misreading as "0"
  • Opioids — consider renal function, prescribe naloxone when initiating
  • Methotrexate — weekly (never daily) for rheumatological use; folate co-prescribed
  • Digoxin — narrow therapeutic index; check renal function and potassium
  • Aminoglycosides — gentamicin; TDM essential; nephrotoxic and ototoxic
  • Lithium — narrow therapeutic index; TDM, renal monitoring

Common Prescribing Errors

  • Prescribing to a patient with a known allergy
  • Incorrect dose for renal/hepatic impairment
  • Drug interactions not checked (e.g. warfarin + NSAIDs, SSRIs + tramadol)
  • Failing to prescribe VTE prophylaxis for admitted patients
  • Prescribing nephrotoxic drugs without checking eGFR
  • Omitting regular medications on admission (medication reconciliation)
  • Using abbreviations that can be misread (e.g. "U" for units)

Useful Resources

  • BNF — bnf.nice.org.uk (free with NHS OpenAthens)
  • BNFc — bnfc.nice.org.uk (paediatric dosing)
  • NICE guidelines — nice.org.uk/guidance
  • Renal Drug Database — renaldrugdatabase.com
  • Stockley's Drug Interactions — via OpenAthens