It is the nature of the game that for reasons of space, not everything can be explained in a review article—for this reason we thank Koch, Dreisbach, and Fulop for their additional comments on our article (1). At this point we should immediately point out that diabetes mellitus is often—but by no means always—associated with olfactory dysfunction (2) and that olfactory dysfunction is not considered an early indication of diabetes mellitus (3)—although unexplained olfactory dysfunction can be an preliminary indication of cognitive impairments (3). As regards the effectiveness of theophylline, controlled and randomized trials are lacking, with the result that to date, theophylline is not considered as sufficiently proved according to relevant international consensus work (4)—among other reasons, in spite of the mentioned and very interesting open label clinical study. In this context the results of further studies of the treatment of olfactory dysfunction are eagerly awaited. We thank our correspondents once more for their additional comments—the treatment of olfactory dysfunction is currently a very dynamic area.
Footnotes
Conflict of interest statement
TH has received financial support from the Smell and Taste Lab, Geneva, Switzerland and from Takasago. He has received consultancy fees from Primavera, Oy-Mittelberg. TH is a committee member of the Olfactology/Gustology Working Group of the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery. He has received support in the form of donations in kind from Burghart, Holm, and aspuraclip, Schönefeld.
References
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