Cytomel-induced coughing

[LPMcGuire]

In late May '09 my doc added Cytomel (first 25mcg and now 12.5mcg) to my Levothyroxine.  Since then I've been able to reduce my Levo from 75, to 66.5 to 50 and now to 25 because my TSH has been dropping (most recently at .33...which is why doc dropped to 25mg of levo).  Here's the thing...ever since I started the Cytomel I've had a persistent dry/tickle cough that seems to originate in my throat at thyroid area.  It was much worse when I was on 25mcg (almost asthma like symptoms), improved dramatically when dose was reduced but it's still an annoying frequent dry cough that can keep me awake. I'm otherwise in perfect health. Healthy diet, regular exercise, non-smoker and moderate alcohol consumption. Could it be a low-level allergic reaction? I'm 50 and have never had any allergies beyond mild hay fever and reaction to sulfa-based antibiotics. The addition of Cytomel is the only thing that seems to have changed.  Please advise.  Thanks!

[Mark Lupo, M.D.]

Would consider stopping the cytomel to see if this helps. Also, we usually use the 5mcg dose of cytomel once or twice a day depending on the situation.  Remember that 1mcg of cytomel is like 4mcg of levo -- so the doses must be balanced properly when making changes/additions.