Volume 195 - Issue 9
Death and morbidity from supratherapeutic dosing of colchicine
Authors: Nicholas A Buckley and Simone O P Rossi
Med J Aust 2011; 195 (9): 517. || doi: 10.5694/mja11.11174
Published online: 7 November 2011
Published online: 7 November 2011
To the Editor: The letter from Smith and colleagues in the 6 June 2011 issue of the Journal1 highlights the potential toxicity of colchicine, even when used in the therapeutic doses recommended in the current product information (PI).2 This in turn highlights how important it is that all medicines have PI that continues to be maintained with the most clinically accurate and up-to-date information. The current system for maintaining PI seems to break down most significantly with out-of-patent, “grandfathered” and “orphan” medicines.3
During 2009, we identified an important change in the recommended dose in the American PI for colchicine through our usual processes of scanning the medical literature (including the websites of drug regulatory agencies). Colchicine is an out-of-patent medicine. The American study underpinning the American PI changes was sponsored by a different company and used a strength of colchicine tablet (600 μg) not available in Australia.4 The local sponsor companies were contacted at the time, but did not plan to update their Australian PI. Amending a PI is a costly and lengthy process, and the expense is hard to justify for an inexpensive and relatively low-use product. We updated the Australian medicines handbook dosing information5 and then wrote to the Therapeutic Goods Administration (TGA) suggesting the PI change could be initiated by them in the public interest.
As yet, we have not received a response from the TGA and the dose in the PI remains unchanged. Despite its limitations in cases such as these,3 the PI forms the backbone of default dosing and drug interaction data in electronic prescribing software in Australia.6 We hope that Smith and colleagues’ letter might not only help prompt a change to the Australian PI for colchicine, but also a reconsideration of whether a more proactive approach is warranted for updating PI dosing and safety information for orphan drugs.
Competing interests
No relevant disclosures.
References
- Smith MWH, Roberts DM, Ritson SM, Day RO. Death and morbidity from supratherapeutic dosing of colchicine [letter]. Med J Aust 2011; 194: 612-613. CBBEDDCC
- Approved product information. Colgout. 2009. http://www.medicines.org.au/files/aspcolgo.pdf (accessed Apr 2011).
- Stockigt JR. The quality of medication information in Australia: the need for more clinical expertise and accountability [editorial]. Med J Aust 2009; 190: 110-111. CBBFAEAD
- Terkeltaub RA, Furst DE, Bennett K et al. High versus low dosing of oral colchicine for early acute gout flare: Twenty-four-hour outcome of the first multicenter, randomized, double-blind, placebo-controlled, parallel-group, dose-comparison colchicine study. Arthritis Rheum 2010; 62: 1060-1068.
- Australian medicines handbook: AMH July 2010 edition. Adelaide: AMH, 2010.
- Sweidan M, Reeve JF, Brien JA, et al. Quality of drug interaction alerts in prescribing and dispensing software. Med J Aust 2009; 190: 251-254. i1142881