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Hi Sue, The ringing in the ears is called Tinnitus. It can be a side effect of medications (check what you are taking) or for me, it can also be a sign that a migraine is on the way. It could also mean a number of many other things, depending on other symptoms you may have.
Ringing in the ears, or tinnitus, can be so annoying that a person with it can't sleep, think or work. It's a common problem for veterans returning from Iraq and Afghanistan. But tinnitus can also start for no apparent reason. That's what happened to Mark Church.