Effects of pentoxifylline on olfactory sensitivity: a postmarketing surveillance study.
OBJECTIVE
To investigate the effect of pentoxifylline, an unspecific phosphodiesterase inhibitor, on olfactory function.


METHODS
Longitudinal study.


METHODS
Nineteen patients who received pentoxifylline to treat inner-ear conditions.


METHODS
Evaluation of olfactory function (ie, odor threshold, odor discrimination, and odor identification) before and after administration of pentoxifylline and assessment of nasal airflow.


RESULTS
Administration of pentoxifylline had no significant effect on nasal airflow (P = .84). After administration of pentoxifylline, patients demonstrated a decrease in odor threshold toward lower odor concentrations (P = .01). The odor threshold shift after administration of pentoxifylline was more pronounced in younger patients than in older patients (correlation between age and change in odor threshold: r = -.72; P = .001). No such changes were observed for suprathreshold olfactory tasks (odor discrimination and odor identification). Six of the 19 patients were found to have hyposmia. Two patients demonstrated a clinically significant decrease in odor threshold after drug administration.


CONCLUSIONS
The present findings may indicate a role for pentoxifylline in the treatment of olfactory loss. Double-blind, placebo-controlled studies are needed to verify whether pentoxifylline can improve olfactory sensitivity in patients with olfactory disorders.
Gudziol
Volker
V
Smell & Taste Clinic, Department of Otorhinolaryngology, University of Dresden Medical School, Dresden, Germany.
Hummel
Thomas
T
D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007759:Labyrinth Diseases / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010431:Pentoxifylline / Q000627:therapeutic use*; D010726:Phosphodiesterase Inhibitors / Q000627:therapeutic use*; D011358:Product Surveillance, Postmarketing / Q000379:methods*; D011446:Prospective Studies; D025363:Rhinomanometry; D012903:Smell / Q000187:drug effects / Q000502:physiology*; D016896:Treatment Outcome; D055815:Young Adult
D010726:Phosphodiesterase Inhibitors; D010431:Pentoxifylline