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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.
Nearly 12 million Americans suffer from tinnitus, ringing in the ears that can stop and start or continue non-stop. In addition to ringing the sound can resemble a roar, squeal, whine, buzz, click, hiss, or hum and can affect one ear or both.