The most common adverse effects of intranasal steroids consist of local irritation, with burning and stinging of the nasal mucosa. Approximately 5–10% of patients using these drugs for 2 weeks or longer experience some degree of nasal bleeding, usually consisting of flecks of blood that are seen after forceful blowing of the nose. This problem can be stopped by taking a 3- to 5-day break from the intranasal steroid spray plus the use of a nasal moisturizer before restarting the medication at a lower dose.
Systemic effects with an intranasal steroid are quite rare. These medications have been carefully studied in order to determine whether they have any suppressive effects on the function of the adrenal glands; these studies have universally shown no effects. In children, the concern of greatest theoretic importance is suppression of growth. One-year studies with mometasone furoate, fluticasone propionate, and budesonide have failed to show any loss of growth in children between 3 and 11 years of age.
In adults, epidemiologic surveys performed to assess the effects of an intranasal steroid on the eyes, including glaucoma and cataracts, have also shown no effects. Taken together, intranasal steroids as a class appear to be extremely safe and have little potential for systemic side effects.