Professor J. Turnidge, Infectious disease physician, comments:
Dr Skyring's letter highlights the dilemma faced by many practising clinicians: do I change my practice because of increasing reports of adverse reactions when the drug has a number of advantages?
He points out the significant benefits of nitrofurantoin and is rightly concerned that patients have been put off by recent publicity. For nitrofurantoin, the rates of adverse reactions are low, but some of these reactions are troublesome.
The reaction of most recent concern is peripheral neuropathy, although this problem has been known for many years. It is most likely in the elderly and others with reduced renal function. Of equal concern is immune-mediated hepatotoxicity, which most often resolves after cessation, but which can be fulminant. A third problem is pulmonary toxicity that can mimic pulmonary fibrosis.1
There are other serious reactions to nitrofurantoin, but the question remains as to whether they are more frequent than with other drugs used for prophylaxis against urinary tract infections, such as trimethoprim with or without sulfamethoxazole. Without a clear picture of the comparative toxicities of drugs taken over the longer term, it is not possible to make sensible recommendations about which drugs are favoured. The best way of dealing with the dilemma is to discuss the benefits and harms of all options with the patient. Dr Skyring should note that nitrofurantoin is still recommended in the current version of Therapeutic Guidelines: Antibiotic.
