Revised: 11 June 2013
Website: Feb 2009
Prescriber Update 2009;30(1):1
Four brands of levothyroxine now have Ministerial consent for distribution in New Zealand. These brands are Eltroxin (GlaxoSmithKline), Synthroid (Abbott), Goldshield Levothyroxine, and Eutroxsig (Sigma). The Eltroxin and Goldshield Levothyroxine brands are fully subsidised by PHARMAC.
Prescribers are reminded that the different brands of levothyroxine are not interchangeable. This
a change in brand will require thyroid function monitoring, and in some cases dose adjustment. Prescribers are also reminded to specify the brand of levothyroxine on each prescription to ensure the correct brand is dispensed for each patient.
The Centre for Adverse Reactions Monitoring (CARM) continues to receive adverse reaction reports for all brands of levothyroxine available in New Zealand; however the number of reports has tailed off in recent months. As at 31 December 2008, CARM had received 1384 reports for Eltroxin, 9 reports for Synthroid, and 5 reports for Goldshield Levothroyxine. Adverse drug reactions to Eltroxin have not been reported to the same extent in other countries where the new formulation is used.
For further information on Eltroxin, the actions taken by Medsafe in response to the increased number of adverse reaction reports, and Medsafe’s evaluation process, please see: http://www.medsafe.govt.nz/hot/alerts/EltroxinInfo.asp
Prescribers are also reminded to continue to report adverse reactions to all levothyroxine brands to CARM.