The diagnosis of rhinitis medicamentosa was made in 130 patients seen over a 10 year period from July 1967 to June 1977. There was an incidence of 1% in our otolaryngological practice. Patients had been taking the causal medication for an average of 21.4 months. There were 73 males and 57 females with the peak incidence in young and middle-age adults. The primary offending medications were decongestant nasal sprays in 85 patients, decongestant drops in 33, and a combination of these drugs in 12 patients. The major reasons for self-medication were 1. deviated nasal septum in 40 patients, 2. an acute upper respiratory infection in 33, 3. allergy in 18, 4. miscellaneous causes in 24 and 5. unknown in 15 patients. The initial management in addition to avoidance of the medication consisted of systemic antibiotics, decongestants, antihistamines, and sedatives depending on the severity of the rhinitis and the presence of secondary infection. Later treatment consisted of correction of the deviated septums, allergic management, and supportive care. Eight patients were considered to have complications of the disease by development of chronic ethmoiditis and nasal polyposis. The pharmacologic properties of the causal agents are thoroughly reviewed as they relate to the pathogenesis of this disease. It is felt that the ready commercial availability and limited clinical value of the topical nasal sprays and drops represents a certain risk to all patients using them.