Trust Policy and Procedure Substitution of Medicines Policy Document ref. no: PP(17)210 For use in: For use by: For use for: Document owner: Status: All clinical areas Pharmacists and authorised Pharmacy Technicians For use in ensuring that Trust prescribing meets the medicines management agenda of the Trust in an efficient manner Chief Pharmacist Approved Contents Page Purpose of guideline 1 General Principles 1 Recommendation and procedures 2 1) Generic substitution 2 2) Therapeutically equivalent substitution 2 3) Rationalisation of antibiotic time of administration 2 4) Rationalisation of time of administration of other medication 3 5) Miscellaneous substitutions 4 6) Specific substitution documents 4 Documentation 4 Rational for main recommendations 4 Document configuration 5 Purpose of the Guideline This document sets out how and when a prescription for a medicine may be amended by a Pharmacist or Pharmacy Technician (who has been assessed as competent to act under this policy, after discussion with a Pharmacist) General Principles It is agreed by the Trust that under certain circumstances it is appropriate for a pharmacist to change a patient s in-patient or out-patient prescription. Any change made must not conflict with the interests of the patient and should comply with the Summary of Product Characteristics (SPC) recommendations. Examples given below are not exhaustive, they demonstrate the scope of the type of substitutions that may be made Source: Chief Pharmacist Status: Approved Page 1 of 5
Recommendations and procedures The change of prescription will be either:- 1. Generic Substitution A change from a branded preparation to the same generic medicine (generic substitution). Generic prescribing is the norm in hospital practice and is reflected in the contents of the Hospital Formulary and the Trust s Policy for the Use of Medicines. It is accepted that under certain circumstances generic substitution is inappropriate, particularly in areas where the bioavailability of branded and generic products differs significantly (e.g. Antiepileptics). If there is any doubt concerning the suitability of the substitution the prescriber will be contacted by the Pharmacist 2. Therapeutically Equivalent Substitution The substitution of one medicine for another therapeutically equivalent medicine. This will allow non-formulary or unavailable preparations to be substituted to rationalise stock and enable therapy to start more quickly. If there is any doubt concerning the suitability of the substitution the prescriber will be contacted by the Pharmacist:- Oral Quinine Sulphate for Quinine Bisulphate (and change of dose from 200mg to 300mg) Oral and IV/IM Amoxicillin for Ampicillin (and change from QDS to TDS, where appropriate) Oral Oxytetracycline for Tetracycline Generic Ibuprofen 5% Gel for any topical NSAID prescribed Oral Sando-K Tablets for Slow K or Effervescent Potassium Tablets (and amend dose appropriately). Peptac liquid for Gaviscon preparations 3. Rationalisation of Antibiotic Time of Administration A change of timing or frequency of administration of any antibiotic to achieve more rational drug therapy. Examples include:- Oral and IV/IM Amoxycillin from four times a day to three times a day Metronidazole Suppositories, reduce frequency of administration from three times a day to twice a day after 72 hours Amendment of the times of administration of any antibiotic prescription to ensure the prescription meets BNF prescribing frequency recommendations Source: Chief Pharmacist Status: Approved Page 2 of 5
4. Rationalisation of Time of Administration of Other Medication A change of timing of administration of the following products to achieve more rational drug therapy:- Oral Isosorbide Mononitrate timing of doses to 8am and 2pm for nonmodified release preparations Morphine Sulphate SR preparations - 12 hourly dosage interval Simvastatin/Pravastatin/Fluvastatin/Rosuvastatin/Bezafibrate SR timing of dose at night Phenelzine/Amantadine/Selegiline - timing of last dose of the day to 4pm Cholestyramine timing of doses to avoid other drugs whose absorption may be reduced Antacids timing of doses to avoid any other drugs whose absorption may be reduced Disodium Etidronate/Alendronate/Risedronate timing of dose to avoid food and milk for two hours before and after dose Stimulant antidepressants timing of dose to morning Alendronic acid/risedronate Frequency of once weekly doses to once a week, if inadvertently prescribed daily Alendonic acid or Risedronate once a week in combination with Calcium Carbonate indication that Calcium Carbonate is not to be taken on the same day as the Alendronic acid or Risedronate Diuretics Timing of last dose of the day, in patients without a urinary catheter, to 2pm Iron preparations Changing iron salt prescribed to Ferrous Fumarate for solid dose forms or Sodium Feredetate for liquid administration to provide the equivalent daily elemental iron intake Iron preparations - Changing of timing of doses to avoid being given at the same time of day as a quinolone antibiotic. Dipyridamole SR 200mg Capsules twice a day, changed to Dipyridamole liquid 100mg three times a day for patients with a proven swallowing deficit needing a liquid preparation Levothyroxine Change of time of administration to before breakfast Quinolone antibiotics - Amend time of administration to coincide with breaks in supplemental enteral feed regimes to reduce risk for interaction Phenytoin - Amend time of administration to coincide with breaks in supplemental enteral feed regimes to reduce risk for interaction Source: Chief Pharmacist Status: Approved Page 3 of 5
Insulin Patients on a twice-daily insulin regime change time of dosing to 8am and 6pm Miscellaneous Substitutions: Oral Co-Amoxiclav 375 two tablets three times a day to oral Co- Amoxiclav 625 one tablet three times a day Phenytoin Amend dose to take into account the non-bioequivalence of tablets/capsules to liquid (100mg of tablet/capsule is equivalent to 90mg of liquid) Citalopram Amend dose to take into account the non-bioequivalence of tablets to liquid (10mg tablet is equivalent to 8mg(4 drops) of liquid) Isomeric equivalent drugs Amend non-formulary isomeric drugs to the Trust formulary choice when appropriate e.g: 5mg Levocetirizine to 10mg Cetirizine 5mg Desloratidine to 10mg Loratidine Supply of spacer device for inhalers if appropriate Addition of an appropriate dose when a drug is prescribed PO/IM/IV (e.g. Domperidone, Prochlorperazine). Changing dose of oral Metronidazole 500mg three times a day to 400mg three times a day orally 5. Specific substitution policy documents For specific classes of medicines it may be appropriate for detailed substitution policy documents to be developed. These documents will state any specific detailed action that must occur when the substitution policy is used. These documents will be produced when more specific guidance is necessary to ensure that a substitution process is appropriately managed, for example when a substitution involves the change of the drug and dose to ensure equivalence. Documentation All prescriptions changed as a result of this policy must be clearly annotated as per substitution policy by the substituting pharmacist If a prescriber intentionally prescribes a particular dose regime that falls outside of the usual guidance for the particular drug, they are asked to annotate the prescription with the reason for the non-standard dosing, to ensure that the prescription is not amended under the Substitution of Medicines Policy Rationale for main recommendations This document has been developed to ensure that Pharmacists can appropriately amend a prescription written by a legal prescriber in appropriate limited situations Source: Chief Pharmacist Status: Approved Page 4 of 5
Document Configuration Author(s): Other contributors: Approvals and endorsements: Consultation: Issue no: 7 File name: Supersedes: Equality Assessed Implementation Monitoring: (give brief details how this will be done) Other relevant policies/documents & references: Additional Information: Simon Whitworth, Chief Pharmacist 8.6.17) 1.7.15) 1.5.13) 2.5.12) 4.11.07) Drugs and Therapeutics Committee (Approved 17.1.07) Medical Staff Committee (Approved 10.1.07) Clinical Standards Executive Committee (Approved 9.2.07) All Trust Consultants comments included All Trust Pharmacists comments included Trust Solicitors comments included H:\Personal\Simon\Policies\Substitution Policy\FINAL Substitution of Meds Policy New Trust format May 2017.doc PP(15)210 Yes To be available electronically on the West Suffolk Hospital Intranet Site and also the Pharmacy Department Intranet policy section This policy will be monitored by periodic prescription audit Substitution of medicines policy, West Suffolk Formulary Review Group, March 1996 This document has been updated to reflect current practice. Source: Chief Pharmacist Status: Approved Page 5 of 5