Health professionals should ensure they are prescribing correct doses of colchicine, a treatment for acute gout, after three elderly patients were hospitalised within a fortnight, doctors at St Vincent’s Hospital in Sydney say in a letter published in the Medical Journal of Australia.
All three patients presented with vomiting and diarrhoea, and all had been taking higher than recommended doses of colchicine, wrote the authors, from the Department of Clinical Pharmacology and Toxicology at St Vincent’s. Colchicine is used for patients who cannot take anti-inflammatory drugs, the usual treatment for gout.
The first, an 87-year-old man, had been prescribed 0.5 mg of colchicine daily, but was taking 1.0 mg four times a day. He was found to have low blood cell counts, damaged muscle fibres and liver dysfunction. With treatment, he recovered after five days.
The second, a 67-year-old woman, had been prescribed 1.0 mg of colchicine initially, then 0.5 mg every six hours “until diarrhoea develops” – a dosing regimen that is no longer recommended. She was taking colchicine every hour despite diarrhoea.
She had low blood pressure, rapid breathing and heart rate, and fever. Multi-organ dysfunction developed rapidly and, despite aggressive resuscitation, she died within 24 hours.
The third, a 77-year-old woman, had been prescribed 1.0 mg of colchicine three times daily. She had mild kidney and liver dysfunction, which resolved over four days with treatment.
“A recent randomised controlled trial demonstrated that low-dose colchicine (1.8 mg over one hour) was as effective as a higher dose (4.8 mg over six hours),” Dr Roberts said.
“Further, the adverse effects of the lower dose were similar to the placebo and significantly less than those of the higher dose. Adapting to the Australian formulation, 1.0 mg initially and 0.5 mg one hour later is now recommended.”
Health professionals should be aware of the new dosing recommendations, which are reflected in Australian guidelines, the letter said.
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