A randomised controlled trial of sodium citrate spray for non‐conductive olfactory disorders

• Published in: Clinical otolaryngology 2017-12, Vol.42 (6), p.1295-1302
• Main Authors: Philpott, C.M., Erskine, S.E., Clark, A., Leeper, A., Salam, M., Sharma, R., Murty, G.E., Hummel, T.
• Format: Article
• Language: English
• Subjects: Acetic acid; Administration, Intranasal; Alcohols; Buffers; Butanol; Calcium; Citrates - therapeutic use; Citric acid; clinical trial; Clinical trials; Conductivity; Design analysis; Double-Blind Method; Ethanol; Female; Humans; Intervention; Itching; Male; Medical research; Mucus; Nasal Sprays; Nose; Odors; Olfaction disorders; Olfaction Disorders - drug therapy; Olfactory thresholds; Patients; Pharyngitis; Pharynx; Phenylethyl alcohol; Randomization; Side effects; smell; Sodium; Sodium citrate; Thresholds; Treatment Outcome; viral respiratory tract infections
• ISSN: 1749-4478; 1749-4486
• DOI: 10.1111/coa.12878

Objectives Previous research has suggested that sodium citrate improves hyposmia by decreasing mucus calcium levels in the nose. This study aimed to confirm or refute this effect in a single application and assess potential side‐effects. Design Study design was a randomised double‐blind controlled trial of sodium citrate nasal spray (intervention) vs sterile water (control). Fifty‐five patients with non‐conductive olfactory loss were randomised to receive the intervention or placebo. Setting Tertiary care clinic. Main outcome measures The primary outcome measure was improvement in measured olfactory thresholds for phenyl ethyl alcohol (PEA) over 2 hours. Other outcome measures assessed were improvement in olfactory thresholds in 1‐butanol, eucalyptol and acetic acid; number of responders with a clinically relevant response in each arm; and adverse effects. Results A significant effect was seen in the intervention arm for PEA and for 1‐butanol and eucalyptol when compared to the control arm (P