Endocrine Abstracts

Directly Observed Therapy (DOT) is the World Health Organization standard used for tuberculosis treatment, where a trained health worker watches the patient swallow every dose. It can be used for patients receiving doses of Levothyroxine of more than 2 μg/kg with persistently increased TSH levels as they are considered to have thyroid deficiency refractory to treatment. Poor adherence is the most common cause of failure of therapy and if this is suspected, a supervised test may be helpful. We present four patients with hypothyroidism on doses of levothyroxine which varied from 200 mcg to 650 mcg and TSH between 19.4 and 39. They all underwent an observed administration of 1000 μg of levothyroxine with blood tests at baseline and at intervals up to 240 min on day one. Therapy was then continued weekly for four weeks with measurement of TSH and T₄ levels. All patients had a peak two-fold increase from baseline of their T₄ at 240 min after administration of 1000 μg of levothyroxine. The subsequent results over the course of the 4week supervised dosing showed TSH stabilise within normal limits. The rapid rise in the T₄ level after taking the drug essentially ruled out malabsorption of the drug. This simple supervised dosing of levothyroxine can potentially be administered in primary care setting where most patients with hypothyroidism are managed, to evaluate the discrepancy between laboratory results of elevated TSH despite supraphysiological levothyroxine doses before referral for specialist review. If patients continue to show poor compliance then thyroxine administered once weekly under supervision can be offered. Directly Observed Therapy has the advantage of close monitoring that may improve adherence. On the other hand, it moves away from the adherence models of communication with cooperation between patient and provider which could make adherence worse if rigidly applied. Cost of drugs vs resources would need to be evaluated.