Canterbury DHB


24 November 2015 (Release of 20th Edition)

In This Section

Preferred Medicines List

Antimicrobial Guidelines

Pharmacology Guidelines

Preferred Medicines List

Gastrointestinal System



  • Mylanta™ is now Mylanta P™

Antispasmodics and Motility Stimulants

  • domperidone - QT prolongation comments amended to exclude higher doses
  • hyoscine butylbromide - added an anticholinergic comment
  • mebeverine - added

Ulcer Healing and Reflux Medicines

  • omeprazole - added a new link to IV infusion in GI bleeds guideline

Antidiarrhoeal Medicines

  • loperamide – added lower dose comment

Steroids, Glucocorticoids

  • steroids - added equivalency comment

Treatment of Inflammatory Bowel Disease

  • mesalazine – doses changed
  • adalimumab – added a maintenance dose
  • infliximab – added a link to the dosing form
  • methotrexate – added a link to HQSC high risk medicine alert


  • added advice to prescribe laxatives regularly with opioids
  • bulk forming - deleted first line comment
  • phosphate enema – added a comment about different Fleet enemas

Oesophageal Varices and Hepatic Encephalopathy

  • new section containing terlipressin (changed dose expression), nadolol and lactulose

Cardiovascular System


Potassium-Sparing Diuretic

  • amiloride - deleted

Anti-Arrhythmic Drugs

  • flecainide - added drug concentration monitoring advice

Beta-Adrenoceptor Blocking Drugs

  • bisoprolol - added
  • carvedilol - adjusted dose
  • metoprolol - added dosing advice and an alert

Calcium Channel Blockers

  • perhexiline - added advice on dosing associated with CYP2D6 and removed PHARMAC restrictions in line with the Pharmaceutical Schedule

Potassium Channel Activators

  • nicorandil - removed PHARMAC restrictions in line with the Pharmaceutical Schedule

Oral Anticoagulants

  • warfarin - clarified different brands and added an alert

Respiratory System


  • beclometasone - added information about different brands of inhalers


  • cetirizine - increased dose


  • New section showing inhaler pictures

Central Nervous System



  • melatonin - added

Antipsychotic Drugs

  • levomepromazine (methotrimeprazine) - added
  • ziprasidone - deleted

Mood Stabilisers

  • lamotrigine - added dosing advice

Central Nervous System Stimulants

  • atomoxetine - deleted

Drugs Used in Nausea and Vertigo

  • domperidone - QT prolongation comments amended to exclude higher doses
  • levomepromazine (methotrimeprazine) - added
  • ondansetron - added indication and constipation advice


  • paracetamol - added weight and dosing advice
  • paracetamol/codeine - added combination use advice

Opioid Analgesics

  • added regular laxative advice
  • fentanyl - added a link to HQSC high risk medicine alert
  • morphine - added clarification around immediate vs slow release preparations
  • oxycodone - added clarification around immediate vs slow release preparations
  • opioid antagonist naloxone - added doses

Treatment of Acute Migraine Attack

  • sumatriptan - added more explicit doses


  • diazepam - added
  • lorazepam - added

Drugs Used in Parkinsonism and Related Disorders

  • ropinirole - added a note about restless legs
  • benzatropine - added a note about reversal of extra-pyramidal adverse effects of dopamine antagonists

Opioid dependence

  • buprenorphine/naloxone - added


Adjunctive Therapy for Beta-lactams

  • probenecid - moved to IV to PO switch

Antianaerobic Agents

  • metronidazole - changed dosing and deleted suppositories

Endocrine System


Male Sex Hormones and Antagonists

  • testosterone cypionate - added

Anterior Pituitary Hormones

  • tetracosactrin - added comment and link for Synacthen™ test

Posterior Pituitary Hormones

  • terlipressin - changed dose expression

Obstetrics, Gynaecology and Urinary Tract Disorders

Drugs Used in Urinary Tract Disorders

  • imipramine - added QT prolongation comment

Malignant Disease and Immunosuppression


  • added doses throughout

Nutrition and Blood


Iron-Deficiency Anaemia

  • ferric carboxymaltose - added

Electrolyte and Water Replacement and Potassium Removal

  • Resonium A™ - added dosing advice for rectal administration
  • Plasmalyte 148™ - added the ‘in glucose’ preparation


  • zinc - now expressed as elemental

Musculoskeletal and Joint Disease


Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)

  • added a comment about parecoxib in theatre and avoidance of other NSAIDs for 24 hours

Disease Modifying Anti-Rheumatic Drugs

  • etanercept - added a TB reactivation comment

Drugs used to Manage Gout

  • allopurinol - added a urate target and increased the upper dose




  • reviewed - no major changes

Ear, Nose and Oropharynx


Drugs Acting on the Ear

  • added increased upper dose to all

Drugs Acting on the Oropharynx

  • benzydamine - added a maximum for lozenges
  • Strepsils™ - deleted



Emollients and Barrier Preparations

  • Sorbolene+glycerin - added
  • QV™ - deleted

Topical Corticosteroids

  • added a new classification of potency

Preparations for Psoriasis

  • calcipotriol/betamethasone - added

For Acne

  • adapalene - added

Scalp Preparations

  • added a new classification of potency for steroids

Anti-Infective Skin Preparations

  • malathion/permethrin/piperonyl - added

Antimicrobial Guidelines

Probenecid as a “booster” of flucloxacillin concentrations

This section has been revised and is now housed within the Intravenous (IV) to Oral Switch section at the front of the Antimicrobial Guidelines.

The strategy of using probenecid to “boost” flucloxacillin concentrations is best restricted to facilitate an earlier IV to oral switch, and to assist compliance with oral dosing on discharge.

Refer to Antimicrobial Stewardship bulletin CDHB Antimicrobial Guidelines – Pink Book October 2015 online update (Oct 2015 No. 015) for further information.

Cholecystitis/cholangitis and acute peritonitis

Empiric antimicrobial choice for these indications remain unchanged. However, the statement “enterococci are resistant to cephalosporins and should be covered by amoxicillin” has been removed to reduce confusion when treating patients with penicillin allergy who should not receive amoxicillin. Enterococci are uncommonly implicated in these infections. However, Infectious Diseases (ID)/Clinical Microbiology review is recommended for patients who are on a regimen without enterococcal cover (e.g. cefuroxime and metronidazole) who are slow to respond or who have laboratory confirmed enterococcal involvement.

Surgical antimicrobial prophylaxis

This section has been updated in line with recent national and international guidelines. Emphasis is on ensuring that an appropriate antimicrobial is given in an adequate dose (higher doses are often being recommended) at the optimal time (usually within 60 minutes pre-incision). Avoidance of unnecessarily broad spectrum agents helps reduce complications such as development of resistant organisms and C. difficile diarrhoea.

Metronidazole dosing

Twice daily dosing (IV 500 mg or PO 600 mg) for most surgical indications is now recommended in line with pharmacokinetic and minimum inhibitory concentration data, clinical studies and international guidelines. Refer to Antimicrobial Stewardship bulletin Metronidazole - twice daily oral dosing for most indications (Oct 2015 No. 016) for further information.

Aspiration pneumonia

Metronidazole is no longer recommended to be given with piperacillin/tazobactam for treatment of severe/life-threatening aspiration pneumonia as the latter agent provides sufficient anaerobic cover on its own. Unnecessary doubling up on antimicrobial cover exposes the patient to more adverse effects without added benefit.

Diarrhoea – antimicrobial associated

Infectious Diseases review is recommended for all patients with C. difficile diarrhoea, aside from those with mild disease who are being managed with cessation of antimicrobials alone. For severe disease, vancomycin PO 500 mg QID is to be used alone (dual therapy with metronidazole is no longer recommended).

Urinary tract infections in pregnancy

Both the cystitis and the pyelonephritis guidelines have been revised to focus on narrower spectrum agents in pregnancy, rather than use of unnecessarily broad-spectrum agents like amoxicillin/clavulanic acid. Pink Book guidelines and HealthPathways now align.

Gentamicin/tobramycin and vancomycin dosing/monitoring guidelines

These are now in the Antimicrobial Guidelines section of the Pink Book (previously in the Prescribing Guidelines).

Pharmacology Guidelines

Information about this Canterbury DHB document (227462):

Document Owner:

Not assigned (see Who's Who)

Last Updated:

Next Review Due:


Note: Only the electronic version is controlled. Once printed, this is no longer a controlled document.

Topic Code: 227462