Thyroid status may affect the rate at which
theophylline is metabolised. In hyperthyroidism it is increased, and so patients require higher
theophylline dosages. As
thyroid function is corrected (e.g. with carbimazole)
theophylline metabolism decreases and so smaller doses are needed. Two case reports describe
theophylline toxicity in patients being treated for hyperthyroidism.
Monitor the outcome of resolving hyperthyroidism, checking for
theophylline adverse effects (headache, nausea, palpitations). Monitor
theophylline levels and adjust the dose as necessary.