Can fluticasone propionate cause impaired sense of smell if using the spray more often than once a day? can it cause permanent loss of smell?

While it could cause some dryness of the nasal membranes, I haven't seen loss of smell but it's best to use the lowest amount of sprays that control symptoms. Many people have used such corticosteroid nasal spray long-term without problems. Your pharmacist may have more information about this question.

Would not expect fluticasone to be the culprit that impairs sense of smell, and would wonder about alternative causes. Best you see an otolaryngologist and have this fully investigated. Would suggest including imaging over base of skull just to be complete.