Table 1.

Causes of olfactory impairment, treatment options and possible therapeutic targets.

Cause	Current treatment options	Potential therapeutic targets
Rhinosinusitis	Maximal medical therapy; endoscopic sinus surgery	Olfactory cleft inflammation
Genetic ciliopathies	None	Gene replacement via viral gene therapy
Post-viral olfactory disorder	Olfactory training therapy	Inflammation; Basal cell signaling pathways
Head injury	Supportive	Neuron degeneration; Glial scarring
Presbyosmia	Supportive	Basal cell signaling pathways; Basal cell replacement