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Commonly prescribed drugs in hospital


You must know these:

  • Cardiac arrest: DC shock 150J biphasic, adrenaline 1mg IV (10ml of 1 in 10,000), amiodarone 300mg IV (if shockable rhythm)
  • Anaphylaxis: adrenaline 0.5mg IM (0.5ml of 1 in 1000), hydrocortisone 200mg IV, chlorpheniramine 10mg IV
  • Seizure: lorazepam 4mg IV (or if no IV access, diazepam 10mg PR)
  • Hypoglycaemia: 10% glucose 200ml IV or 20% glucose 100ml IV (repeat as needed), or glucagon 1mg IM (if no IV access)
  • Hyperkalaemia: 10ml of 10% calcium chloride IV over 15 minutes THEN 50ml of Glucose 50% containing 10units of Actrapid insulin infused over 20 minutes.
  • Bradycardia: atropine 500mcg IV (repeat every 3-5 minutes to maximum of 3mg if needed)
  • SVT: adenosine 6mg IV (can be followed by 12mg, then another 12mg if unsuccessful)
    • NB: must be given as a bolus and flushed quickly via a large vein.
  • Pulsed VT (without life threatening features): amiodarone 300mg IV over 10-60 minutes
  • Rapid tranquillisation of agitated patient at risk of self harm to self / others: lorazepam 1-2mg PO/IM or olanzapine 5-10mg PO/IM
  • Tranquilisation notes: use oral where possible; give half dose in elderly or renal impairment


Analgesic ladder

  1. Non-opioid (paracetamol or NSAID)
  2. Weak opioid (e.g. codeine) ± non-opioid
  3. Strong opioid (e.g. morphine) ± non-opioid
  • Paracetamol 1 gram PO/IV, PRN 4-6 hourly (max. 4 grams), or QDS
  • Ibuprofen 400mg PO, QDS (contraindicated if gastritis history)
  • Co-codamol 8/500 or 30/500 2 tablets PO, PRN 4-6 hourly (max. 8 tablets), or QDS
  • Codeine 30-60mg PO, PRN 6 hourly (max. 240mg), or QDS (if regular
  • Tramadol 50100mg PO, PRN 4-6 hourly (max. 400mg), or QDS
  • Morphine sulphate oral solution (Oramorph) 10mg/5ml 5-10ml PO, PRN 2 hourly (reduce dosing interval or use alternative in renal impairment)
  • Morphine 1-10mg IV/IM/SC, PRN 4 hourly (max. 60mg; reduce dosing interval or use alternative in renal impairment)
    • As a rough guide, the IV dose of morphine is 0.1mg/kg. So for a 70kg person, the dose would be 7mg. If given in a non-monitored environment (theatres / intensive care / resus) this should be given with caution.
  • Morphine sulphate modified release tablets (Zomorph/MST) 10-60mg PO, 12-hourly
  • Morphine PCA (patient-controlled analgesia) 1mg bolus, 5 minute lockout (button only to be pressed by patient)

Opioid conversions

  • IV morphine = 3 x stronger than oral morphine
  • Subcutaneous morphine = 2 x stronger than oral morphine
  • Oxycodone = 2 x stronger than morphine (if same administration route)
  • Fentanyl patch: 24 hour oral morphine dose (in mg) ÷ 3 = fentanyl patch dose in mcg/hour (safe in renal impairment)
  • Buprenorphine patch: 24 hour oral morphine dose (in mg) ÷ 2.3 = buprenorphine patch dose in mcg/hour
  • Subcutaneous alfentanyl = 30 x stronger than oral morphine (safe in renal impairment)

Concept of background and breakthrough analgesia

For patients with ongoing severe pain, you should prescribe regular background (long-acting) analgesia with PRN breakthrough (short-acting) analgesia. The initial dose of background analgesia should be equivalent to the average dose of PRN analgesia they are currently needing over 24 hours. Breakthrough analgesia should be about 1/6 the dose of the total background analgesia dose. Prescribe this 4-hourly PRN. For example, if a patient has been needing 60mg Oramorph a day, convert them to 30mg MST BD, and also prescribe 10mg Oramorph PRN 4-hourly for breakthrough pain.

Subcutaneous PRN medications in palliative patients (all PRN 1-2 hourly)

  • Morphine 2.5mg (max. 20mg/24 hours) – for pain/SOB (use alternative in renal impairment, e.g. fentanyl/oxycodone)
  • Midazolam 2.5mg (max. 20mg/24 hours) – for anxiety and agitation (reduce dose in renal impairment)
  • Hyoscine butylbromide 20mg (max. 120mg/24 hours) – for bronchial secretions
  • Haloperidol 0.5-1.5mg (max. 5mg/24 hours) – for nausea and vomiting

Subcutaneous syringe driver in palliative patient (all over 24 hours)

Tailor to patient’s symptoms – content options include:

  • Morphine 10-20mg – for pain and breathlessness (use alternative in renal impairment, e.g. fentanyl/oxycodone)
  • Midazolam 10-20mg – for confusion without hallucinations (reduce dose in renal impairment)
  • Hyoscine butylbromide 40-120mg – for bronchial secretions
  • Haloperidol 2.5-5mg – for nausea and vomiting; or confusion with hallucinations
  • Cyclizine 75-150mg – for nausea and vomiting
  • Levomepromazine 5-25mg – for nausea and vomiting (2nd line)

Nutritional supplements

  • Fortisip Compact Extra 125ml PO, BD/TDS/QDS
  • Sanatogen A-Z Complete tablets 1 tablet PO, OD
  • Thiamine 100mg PO, BD
  • Vitamin B Compound Strong 2 tablets PO, BD


  • Senna 7.5-15mg PO, ON (stimulant laxative – first line for acute and opiate constipation)
  • Macrogol oral powder (Movicol) 1-2 sachets PO, OD/BD/TDS (osmotic laxative – for faecal impaction)
  • Ispaghula husk (Fybogel) 1 sachet PO, BD (bulk forming laxative – first line for chronic constipation, elderly patients and pregnant patients)
  • Magnesium hydroxide 30-45ml PO, ON (osmotic laxative – often used for post-operative patients)
  • Glycerol 4g suppository 1 suppository PR, STAT (stimulant laxative)
  • Phosphate enema 1 enema PR, STAT (osmotic laxative)


  • Cyclizine 50mg IV/IM/PO, PRN 6-8 hourly (max. 150mg)
  • Ondansetron 4mg IV/IM/PO, PRN 4-6 hourly (max. 16mg) – can cause QT prolongation
  • Metoclopramide 10mg IV/PO TDS (antidopaminergic SEs, so give for maximum of 5 days and avoid if young/Parkinson’s/dyskinesias)

Sleeping tablets

  • Zopiclone 7.5mg PO (3.75mg if elderly), ON (caution in renal impairment)
  • Temazepam 10mg PO, ON (caution in renal impairment)


  • Salbutamol 2.5-5mg NEB, PRN 4-6 hourly (max. 20mg) – can be given more frequently if required 
  • Ipratropium bromide 250-500micrograms NEB, PRN 4-6 hourly (max. 2mg)
  • Prednisolone 30-40mg PO, OD

Correcting electrolytes


  • Mild (>2.5mmol/L): Sando-K 2 tablets TDS x 3/7, or add 20-40mmol/L potassium chloride to each litre of IV fluids
  • Severe (<2.5mmol/L or ECG changes): 40mmol/L potassium chloride in 1L 0.9% saline over 4-6 hours (NEVER >10mmol/hour K+ outside ICU)


1. ECG and cardiac monitoring

2. Calcium gluconate 30ml 10% IV over 15 minutes if ECG changes (consider if severe, i.e. ≥6.5mmol/L, without ECG changes)

3. Actrapid insulin 10 units in 125ml 20% glucose IV over 30 minutes + 10mg salbutamol neb

4. Sodium zirconium cyclosilicate 10g PO TDS for up to 72 hours 


  1. Mild (>1.9mmol/L and asymptomatic): calcium (e.g. Sandocal or Calcichew) 1000mg BD + vitamin D if deficient 
  2. Severe (<1.9mmol/L or symptomatic): calcium gluconate 10ml 10% IV over 10 minutes – can be repeated until asymptomatic and usually needs to be followed by an infusion (50ml 10% calcium gluconate in 500ml 0.9% saline over 12 hours)


  • Replace fluid deficit with 0.9% saline and keep patient well hydrated (continuous IV fluids)
  • Severe (>3.5mmol/L or symptomatic): if calcium stops falling with IV fluids alone, consider IV bisphosphonate, e.g. zoledronic acid 4mg IV, depending on renal function (one-off dose)


  • PO: magnesium aspartate 1 sachet (10mmol) BD x 3/7
  • IV: 5grams (20mmol) magnesium sulphate in 500ml 0.9% saline over 5 hours


  • PO: Phosphate-Sandoz 2 tablets TDS x 3/7
  • IV: Phosphate Polyfusor (50mmol in 500ml) 100-300ml over 12-24 hours depending on weight and severity OR sodium glycerophosphate 10mmol in 500ml 0.9% saline over 12 hours