Nasal decongestants are ones of the most popular and widespread medicines due to high frequency of respiratoryinfections. But on the other hand they are characterized by significant abuse potential for users seeking such effectsas euphoria, psychostimulation, less of appetite and lose the weight.The affections of the cardio-circulation and nervous systems are the most frequent complications after overdosing ofthe nasal decongestants. The development of the strikes in the young age was associated with the nasal decongestantsabuse in every tenth patient.The cases of the malignant arterial hypertension, cerebral hemorrhages, ischemic strokes, heart decompensationafter the nasal decongestants abuse is known as nasal decongestants poisoning. And although the side effects moreoften develop when nasal decongestants are used orally, intranasal way could not be considered as absolutely safe,especially in cases of overdosing.The development of the psychotic disorders is one of the most frequent nasal decongestants adverse effects. Theelderly people with organic brain damage, drug addiction, mental illness are in the risk group for the developmentof psychotic complications.Misuse of the nasal decongestants in children is especially dangerous because of the high risk of the developmentof the life-threatening toxic poisoning. Fatal cases of poisoning were associated with small age of a child, usingseveral medicines with the same ingredient, using decongestants in a daycare setting, mistakes in measuring andidentification the medicine, the absence of the doctor’s prescription, use of the product for adult age.Using nasal decongestants in supine position of the patient may lead to the significantly dose increase inside thenasal cavity and may cause toxic poisoning.Adolescents are quite sensitive to the development of nasal decongestants side effects with such risk factors asage, gender, family income, physical and mental health, use of other medicines and alcohol.The special type of the adverse effects of the long-term using of the nasal decongestants is the rhinitismedicamentosa taking place in adult persons with predisposition to the nasal hyperreactivity. The diagnosis ofthe rhinitis medicamentosa is based on the nasal hyperactivity and swelling of the nasal mucous membrane incombination with poor response on treatment caused or exaggerated by long-term use of topical nasal decongestants.The development of the rhinitis medicamentosa depends on a number of factors such as the type of nasaldecongestants, the type of preservative, the presence of risk factors that determine the patient's predisposition to thedevelopment of nasal hyperreactivity.Here we review the existing literature concerning the adverse effects of the nasal decongestants including thedevelopment of the rhinitis medicamentosa.