The authority listing for terbinafine 250 mg tablets was extended on 1 April 2008 to allow the treatment of Aboriginal and Torres Strait Islander peoples with a dermatophyte infection that has not responded to topical treatment. Effective 1 July 2008, there will also be a new streamlined authority listing for terbinafine 1% cream, allowing for the treatment of fungal or yeast infections in Aboriginal and Torres Strait Islander peoples. 1

Oral terbinafine is associated with rare but serious adverse effects (e.g. blood dyscrasias, liver failure).2-5 Prescribe the tablets only after the cream, if this has not treated the fungal infection. Monitor blood count and liver enzymes if more than 6 weeks of treatment is required. 6

Terbinafine inhibits cytochrome P450 2D6 in the liver and may increase the risk of adverse effects of coadministered drugs that are metabolised by this enzyme (e.g. selective serotonin reuptake inhibitors). The potential for drug interactions may last for months after stopping oral terbinafine (treatment itself can last for up to 6 months) because of its very long half life (about 36 hours). 2,6

The PBAC recommended the listing of these terbinafine preparations under the 2004-05 Budget measure that allows PBS listing of medicines specifically for Aboriginal and Torres Strait Islander peoples. For more information, refer to the NPS RADAR In Brief ' Medicines listed on the PBS for Indigenous Australians' or the Department of Health and Ageing website.

References

  1. Pharmaceutical Benefits Advisory Committee. Public summary document: terbinafine — tablet 250 mg and cream 10 mg per g, 15 g. Canberra: Australian Government Department of Health and Ageing, 2008. http://www.health.gov.au/internet/main/publishing.nsf/Content/pbac-psd-terbinafine-nov07 (accessed 29 February 2008).
  2. Novartis Pharmaceuticals Australia Pty Ltd. Lamisil tablets product information 13 September 2007. Australia.
  3. Adverse Drug Reactions Advisory Committee. Life-threatening blood dyscrasias with oral terbinafine. Australian Adverse Drug Reactions Bulletin 2006;25:3.
  4. Adverse Drug Reactions Advisory Committee. Terbinafine and blood dyscrasias. Australian Adverse Drug Reactions Bulletin 2004;23:3.
  5. Adverse Drug Reactions Advisory Committee. Hepatic reactions with terbinafine. Australian Adverse Drug Reactions Bulletin 2008;27:3.
  6. Rossi S, ed. Australian Medicines Handbook. Adelaide: Australian Medicines Handbook Pty Ltd, 2008.