What is the negative effect of Coreg and Syntrhoid when taken together? I have congestive heart failure and was fitted with a defibrillator in 2006. I also had thyroidectomy in 2004. Among my prescriptions are Coreg Cr 80 mg and Synthroid .112. Instructions for taking these medications indicate that they shuold be monitored. However, my GP has not done so. Please tell me what caution should I should be aware of. Thanks.
NMC