Last reviewed 01/2018
Rhinitis medicamentosa is an iatrogenic condition where rhinitis has developed as a result of inappropriate use of vasconstrictor nasal drops to relieve nasal congestion.
Sympathomimetic decongestants cause vasoconstriction of the nasal mucosal blood vessels providing relief from the symptom of nasal congestion. However, as their effects wear off, secondary vasodilatation occurs causing the sense of congestion to return. This prompts further application of the decongestant and a vicious circle of use develops.
In this condition, rhinitis is thought to be a consequence of tissue hypoxaemia from reduced mucosal blood flow.
Of the sympathomimetrics, ephedrine is the safest to use topically. Agents with more potent vasoconstrictor activity such as oxymetazoline and xylometazoline are more likely to cause a rebound effect. All should be avoided in patients receiving monoamine oxidase inhibitors because of the risk of provoking a hypertensive crisis.