Rhinitis Medicamentosa

• aka rebound congestion
• is inflammation of the nasal mucosa caused by the overuse of topical nasal decongestants.
• can develop as early as 3 days and up to 4 to 6 weeks of use
• intranasal cocaine use has also been reported to cause a similar condition. 

Physiology of Nasal Congestion 

• The nasal mucosa vascular system can divide into :
  • resistance vessels (arterioles) : regulated by α-2 adrenoreceptors
  • capacitance vessels (venous plexus): regulated by both α-1 and α-2 adrenoreceptors. 
• Stimulation of these receptors leads to the decongestants effect by
  • vasoconstriction of the large. venous sinusoids and collecting veins
  • decreased blood flow
  • decreased nasal edema and rhinorrhoea.
• stimulation of parasympathetic nervous system –> the release of local mediators including mast cells, eosinophils, basophils –>stimulates the release of histamine, tryptase, kinins, prostaglandins, and leukotrienes –>overall change in nasal resistance and capacitance vessels ->nasal congestion

Topical Nasal Decongestants 

• Topical nasal decongestants classified as:
  • β-phenylethylamine derivative
  • Imidazoline derivatives.
• β-phenylethylamine derivatives
  • mimic the effects of the sympathetic nervous system stimulation by producing vasoconstriction via the activation of α-1 adrenoreceptors.
  • Rebound vasodilation may occur due to weak affinity towards β–adrenoreceptors.
  • Nasal Decongestants :
    • Phenylephrine HCl:
      • Brand Names:
        • Sudafed PE Nasal Decongestant: Available as tablets and nasal sprays.
        • Dimetapp PE Nasal Decongestant: Available as tablets and nasal sprays.
    • Ephedrine HCl:
      • Brand Names:
        • Sudafed: Available as tablets.
• Imidazolines
  • produces its effect mainly via αc-2  adrenoreceptors.
  • This difference in adrenoreceptor sensitivity makes the imidazoline agents more effective at decreasing mucosal blood flow due to its vasoconstrictive effect to both capacitance and resistance vessels in the nasal mucosa.
  • Imidazole group demonstrates a more potent and longer-acting effect.
    • 0.1% xylometazoline hydrochloride works within a few minutes and lasts up to 10 hours
  • Nasal Decongestants:
    • Oxymetazoline HCl:
      • Brand Names:
        • Drixine: Available as nasal sprays.
        • Sudafed 12 Hour Nasal Decongestant: Available as nasal sprays.
        • Vicks Sinex: Available as nasal sprays.
    • Xylometazoline HCl:
      • Brand Names:
        • Otrivin: Available as nasal sprays (Otrivin Adult, Otrivin Plus).
        • Dimetapp 12 Hour Nasal Spray: Available as nasal sprays.
    • Naphazoline HCl:
      • Brand Names:
        • Naphcon Forte: Available as eye drops (primarily for ocular use, but it shares the same decongestant properties).

Pathophysiology- unknown (Hypotheses)

• Chronic vasoconstriction leads to ischemia of the nasal mucosa, causing interstitial edema.
• Fatigue of constrictor mechanisms results in reactive hyperemia and congestion (tachyphylaxis).
• Alteration in vasomotor tone increases vascular permeability and edema.
• Beta-adrenoreceptor activity outlasts alpha effects, leading to rebound vasodilation.

Symptoms:

• Recurrence of nasal congestion.
• Oral breathing, dry mouth, and snoring.
• Absence of rhinorrhea.
• Occurs with prolonged use of intranasal decongestants.

Signs:

• Nasal mucosa swelling.
• Erythematous and granular appearance.
• Pale and edematous appearance.
• Progression leads to atrophic and crusty nasal membrane.

Treatment / Management

• discontinuation of the topical decongestant
• advice patients that nasal congestion may temporarily worsen upon discontinuation of the topical decongestant so that they do not perceive it as treatment failure.
• Intranasal corticosteroids
  • minimize the symptoms of rebound congestion
• Short-course oral corticosteroids (e.g., prednisone, 0.5 mg per kg for five days)
• Oral antihistamines
• It takes approximately one year for complete recovery in cases of long-term overuse

Complications

• Chronic ethmoiditis
• Atrophic rhinitis
• Septal perforation
• Chronic rhinosinusitis
• Turbinate hyperplasia