Colleen, if you call your pharmacist, they should be able to tell you about instructions for taking on an empty stomach. Looking around the site that Pete linked, though, I found this which mentions both the empty stomach and waiting an hour after taking before eating, as well as the calcium and iron thing.

http://thyroid.about.com/library/howto/htthyroid-drugs.htm

SCC(T2N0M0) part.glossectomy & neck dissect 2/9/05 & 2/25/05.33 IMRT(66 Gy),2 Cisplatin ended 06/03/05.Stage I breast cancer treated 2/05-11/05.Surgery to remove esophageal stricture 07/06, still having dilatations to keep esophagus open.Dysphagia. "When you're going through hell, keep going"