Prescribing Summary Pharmacy Department Learning Objectives Recap prescribing

Prescribing Summary Pharmacy Department

Learning Objectives • Re-cap prescribing errors and near misses (APINCH) • Safely prescribe medications (continuation): • National Inpatient Medication Chart (NIMC) • Discharge prescription- Go through • Overview of PBS system • Resources for information • Principles of Renal dosing • Understanding for Vancomycin dosing • Ask questions anytime!

Prescribing Errors and Near Misses

National Inpatient Medication Chart (NIMC)-Adapted- Front Regular Medications Section Variable Dose Warfarin Dose VTE Prophylaxis Section

National Inpatient Medication Chart (NIMC)-Adapted- Back Prescribing principles “As Required” (PRN) Section Once-only order Telephone order

Discharge Prescription Write duration in days as well a quantity for short course medications Specify days for warfarin dosing DAs require quantity and no. of repeats in words and figures Change combination product back on discharge Ensure prescriber no. is legible. Complete ADR/allergy (medicine and reaction)

Pharmaceutical Benefits Scheme (PBS) • PBS website: www. pbs. gov. au • The website can be found via the Shortcuts menu (Pharmaceutical Benefits Schedule) • Include information about: • If the medication is covered by the PBS, and for what indication • Maximum quantity (and repeats) that can be prescribed • If an authority is required (streamline vs telephone) Exercise to look up on PBS website: 1. Atorvastatin 2. Ciprofloxacin 3. Pregabalin

Pharmaceutical Benefits Scheme (PBS) Authority required benefits fall into two categories 1. Authority required (via phone call) • • Prescribing quantity in excess of the PBS quantity OR Medication has specific criteria as per PBS website Contact then via 1800 888 333 If approval is granted, the operator will give you an authority number that needs to be written on the prescription e. g. Z 1234 AB 2. Authority required (STREAMILINED) (via PBS website) • prescribe a medication that is only subsidised by the PBS for certain indications • Ensure you choose the correct indication and authority number (e. g. 1234) is written on the prescription

Resources REFERENCE Australian Medicines Handbook (AMH) Therapeutic Guidelines (e. TG) Treatment Guidelines Indication Dose Administration guidelines Adverse effects Precautions/ Contraindications Drug interactions MIMs online Australian Injectable Drug Handbook Northern Health policies (PROMPT) **not all drugs have a NH plicy) Antibiotic Guidance PBS website Compatibility information TDM Brands

Ms. Patient PC: 25 year female came into hospital with suspected Osteomyelitis and AKI. • Medical Condition: Epilepsy, spinal surgery (3 months ago). • Allergies: Flucloxacillin- Anaphylaxis • Medication: Carbamezapine CR 200 mg mane.

Impaired renal function You need to prescribed oral Ciprofloxacin for the treatment of osteomyelitis as per sensitivities Her calculated GFR =20 m. L/min • Which resources do you look for dosage adjustment? • Therapeutic Guidelines (e. TG) • Renal Handbook • AMH

Impaired renal function You need to prescribed oral Ciprofloxacin for the treatment of osteomyelitis Her calculated GFR =20 m. L/min

Ms. Patient PC: 25 year female came into hospital with suspected Osteomyelitis and AKI. Both issues have treated and ready for Discharge • Medical Condition: Epilepsy, spinal surgery (3 months ago). • Allergies: Flucloxacillin- Anaphylaxis • Medication: Carbamezapine CR 200 mg mane.

Drug Interactions Discharge: You would like to prescribe Cyproterone with ethinylestradiol 2 mg/35 microg (Diane-35 ED) for Ms. Patient. Current medications: Carbamezapine CR 200 mg mane Where would you look to see if there any drug interactions? 1. 2. 3. 4. AMH Stockley’s Drug Interactions MIMS Micromedex

Drug Interactions You would like to prescribe Cyrproterone with ethinylestradiol 2 mg/35 microg (Diane-35 ED) for a patient on Carbamazepine.

Crushing medications and IV therapy? Your patient has a NG tube which requires all their oral medications to be crushed? Some medications if oral and is bioequivalent to IV can changed over. Your patient is on; 1. Pantoprazole EC 40 mg mane 2. Ceftriaxone 1 g mane Where can you look for information? 1. Don’t Rush to Crush Handbook- Available through Mims Online 2. Australian Injectable Drugs Handbook 3. The Northern Health Medication Protocol

Crushing medications and IV therapy? Your patient is on; 1. Pantoprazole EC 40 mg mane 2. Ceftriaxone IV 1 g mane

Medication Protocol Your Patient is to start IV Vancomycin. Where do you look for information? 1. Local hospital medication protocol 2. Australian Injectable Drug Handbook 3. Micromedex Policy/Procedures (PROMPT)

Medication Protocol TIP: always use the electronic version rather than downloaded version.

Vancomycin • IV: MRSA cover. Oral (NG or PR): C. diff • Why do we still struggle to dose it? • Patient specific, based on… Ø Renal function Ø Weight • Loading • Maintenance • Monitoring • Adjusting • Requires Guidance • https: //guidance. nh. org. au

Principals of renal dosing • These patients have the same • Weight • Height • Creatinine • Is their renal function the same? • No: need to factor in age and gender

Principals of renal dosing • These patients have the same: • Creatinine • Age • e. GFR • Is the e. GFR an accurate estimate of renal function? • No, use the Cockroft. Gault formula to calculate Cr. Cl (or use an online calculator!)

Creatinine Clearance e. TG AMH

Which weight should you use? These patients are both the same weight This patient’s BMI is 15 - actual, but interpret with caution These patients have BMIs within the normal range - actual Reported e. GFR based BSA 1. 73 m 2

Which weight should you use? • Summary • ‘Normal’ weight: Actual BW • Underweight: Actual BW • High BMI & muscular: Actual BW • High BMI & Obese: ideal or lean BW

Other things to consider… • • • Current clinical picture Trends in renal function Urine output How the drug is cleared Toxicity of drug – risk vs benefit Any nephrotoxic agents

Vancomycin-Loading Dosage 95 kg & Cr. Cl: >90 ml/min 55 kg & Cr. Cl: 45 ml/min 75 kg & Cr. Cl 15 ml/min

Vancomycin-Maintenance Dosage 95 kg & Cr. Cl: >90 ml/min 55 kg & Cr. Cl: 45 ml/min 75 kg & Cr. Cl 15 ml/min

Vancomycin- TDM

Vancomycin- Dosage Adjustment 95 kg & Cr. Cl: >90 ml/min 55 kg & Cr. Cl: 45 ml/min 75 kg & Cr. Cl 15 ml/min

Vancomycin Summary • • • Dosed based on weight and renal function For patients of extremes of body weight <50 kg, >120 kg or BMI >35 discuss with ID/AMS Trough levels for monitoring at: – 48 h for Cr. Cl>20 ml/min, GIVE the next dose – 24 h for Cr. Cl<20 ml/min or RRT, WITHOLD next dose until level back • • • Adjust dose based on levels, checking it has been taken at the correct time Linear kinetics Monitor renal function until level is stable, with dose increases If the vancomycin levels are increasing – consider AKI Ask if you’re not sure!

Questions…