The condition you are experiencing may be related to phantosmia, which is characteristic of a potentially unpleasant "phantom" odor that persists over several weeks. Several medical conditions may be involved if this is the case. These include atrophic rhinitis, head trauma and nasal polyps, among others. On the medication side (which is more my expertise), we note that doxycycline can cause this type of reaction in very rare cases. Considering the chronology of events you describe, I think it would be very relevant to consider doxycycline as being involved. Why were you prescribed it? Thank you for the information. I recommend that you speak with your pharmacist (and your ophthalmologist at short notice) tomorrow so that we can find an alternative to Doxycycline. You should also know that it is imperative that your pharmacist (or yourself) notify Health Canada of this effect. It is very, very rare and should be investigated further.