Here is a collection of user reviews for the medication Toprol XL sorted by most helpful. See User Reviews. Report Problems to the Food and Drug Administration. You are encouraged to report negative side effects of prescription drugs to the FDA.
1 Persistent bad breath or a bad taste in the mouth can also be one of the warning signs of gum disease; which is caused by plaque.  Dry mouth. This occurs when the flow of saliva decreases and can be caused by various medications, salivary gland problems or continuously breathing through the mouth.
Bad breath (halitosis) can be caused by a variety of things, including diet, medication, poor oral hygiene, and diseases or conditions such as diabetes, GERD, lactose intolerance, gum disease, and more. Treatment for bad breath depends on the cause. Medications that cause a dry mouth can trigger bad breath. In addition, certain medications, such as triamterene and paraldehyde, have bad breath as a side effect. Causes of bad breath include the following: When a person does not brush or floss their teeth thoroughly, food particles that may remain in the mouth can rot and cause foul odors. In addition, food particles over time can promote the growth of bacteria, which can also cause foul odors.