Hey Veronica,
They only thing I could find was that Opioid-induced respiratory depression resulting from transdermal fentanyl-clarithromycin drug interaction in a patient with advanced COPD.
You may want to read this site. It has some very important information. You cannot drink grapefruit juice or eat a grapefruit while on this patch. You cannot use anything that heats, like a heating pad or it can cause very serious side effects. Please read this site before making your decision. This is a VERY serious drug.
health.yahoo.com/pain-medications/fentanyl-transdermal-skin-patch/healthwise--d00233a1.html