The Editorial Executive Committee welcomes letters, which should be less than 250 words. Before a decision to publish is made, letters which refer to a published article may be sent to the author for a response. Any letter may be sent to an expert for comment. When letters are published, they are usually accompanied in the same issue by their responses or comments. The Committee screens out discourteous, inaccurate or libellous statements. The letters are sub-edited before publication. Authors are required to declare any conflicts of interest. The Committee's decision on publication is final.
Letter to the Editor
Editor, – In June 2003 the Therapeutic Goods Administration (TGA) instructed Sigma Pharmaceuticals to reduce the shelf-lives of Oroxine and Eutroxsig - the Australian brands of thyroxine - from 24 months to 12 months (with refrigeration). This was in light of evidence that their potency was reduced at the end of their shelf-life. Sigma, following consultation with the TGA, has been able to extend the shelf-life of these products to 18 months (with refrigeration), with a maximum unrefrigerated period of 4 weeks (below 25°C).
While Thyroid Australia understands and appreciates the TGA's efforts to ensure the potency of thyroxine for the entirety of its shelf-life, we view the change to refrigeration as a retrograde step in the treatment of hypothyroidism in Australia.
We are concerned that this change could have a negative impact on compliance. In addition, it seems Australia is the only country where thyroxine tablets require refrigeration. In many countries the shelf-life unrefrigerated is much longer than 18 months. This leads Thyroid Australia to question the TGA's approach to remedying potency issues with thyroxine. Addressing the matter by introducing refrigeration places the burden on patients.
Due to thyroxine, hypothyroidism is a readily treatable condition. It enables affected individuals to lead very close to normal lives. This change moves hypothyroidism from a condition that can be easily lived with, to a condition that impinges upon everyday life. In particular, it places limits on travel and spontaneity. We hope that refrigeration is only an interim measure until a more viable long-term solution is found.
President, Thyroid Australia
Sigma Pharmaceuticals, the manufacturer of thyroxine tablets, did not wish to add to the discussion.