New twice daily nitrofurantoin (Macrobid) now available in NZ

Goodfellow Gems Logo

Goodfellow Gems

New twice daily nitrofurantoin (Macrobid) now available in NZ

Nitrofurantoin is now a first-line antibiotic for cystitis, through high concentrations in urine, and is active against most urinary pathogens. It should never be used for patients with pyelonephritis or prostatitis because it does not reach effective concentrations in blood or tissues. It will work in patients with an eGFR<40 and does not need to be restricted to patients with normal renal function.

Previously it has been used  4 times daily for 5 to 7 days. A new twice-daily version is now available and is known as Macrobid (It needs to be prescribed by its trade name to get it to appear in clinical computers. It is fully funded.) The side effects are uncommon and mainly gastrointestinal.1 The advice is for 7 days but 5 days may be sufficient.2 Three days is not sufficient.

This Gem has been approved by Assoc-Prof Mark Thomas of Auckland University.


  1. Nitrofurantoin revisited: a systematic review and meta-analysis of controlled trials. J Antimicrob Chemother (2015) View here
  2. Nitrofurantoin and fosfomycin for resistant urinary tract infections: old drugs for emerging problems Australian Prescriber (2019)  View here

Gems are chosen by the Goodfellow director Dr. Bruce Arroll to be either practice changing or practice maintaining. The information is educational and not clinical advice.

As published in: