Common side effects of Flonase include dryness of the nose, head pain, irritation of the inside of the nose, nosebleed and throat irritation, explains WebMD. Sores or white patches, coughing and trouble breathing, back pain and nausea are additional common side effects named by Drugs.com.
Less common but severe side effects include bronchitis, dizziness, hives, and injury to the mucuous membrane, states WebMD. In preventing overdose, Drugs.com warns patients who miss scheduled doses to skip application when the next scheduled dose is approaching. Patients should also consult their physicians when taking other medications with Flonase, as certain antifungal and antiviral prescriptions may interact with the nasal spray, advises Drugs.com.