A recent research study has shown that sodium citrate (in the form of a nasal spray) could potentially offer temporary improvement in the ability to smell for people affected by post-viral olfactory loss or other non-obstructive causes. The research was undertaken by the University of East Anglia (UEA) and the Smell and Taste Clinic at James Paget Hospital and involved Consultant ENT Surgeon and Fifth Sense trustee Mr Carl Philpott.
How is the spray thought to work?
Calcium is thought to have a role in ‘turning down’ the sense of smell, a bit like a volume control. Sodium citrate is known to ‘bind’ with calcium molecules, and stop them from acting in this way. In the study, a group of people with anosmia or hyposmia were treated with a sodium citrate nasal spray, alongside a control group whose spray contained water. Around one third of the study participants who were treated with the sodium citrate spray experienced some improvement in their ability to smell, which lasted up to two hours, with the effect peaking at 15-30 minutes.
Who could this potentially help?
The study showed that the spray seemed to be most effective in people affected by post-viral olfactory loss, although some people with idiopathic (no known cause) and post-traumatic olfactory loss (PTOL) also showed some improvement. It’s difficult to say why this is, but sometimes there can be more than one factor involved in anosmia or hyposmia. Some cases of idiopathic olfactory loss could have been caused by an undiagnosed virus, which would help explain why the citrate spray results in an improvement. The location and degree of damage caused in PTOL is likely to vary between people, and it is possible that the citrate boosts the function of any olfactory neurones and nerves that are still intact.
Further studies are needed to establish the effectiveness of sodium citrate in daily use as a longer-term treatment.
I want to try this myself, is it possible to purchase sodium citrate spray?
This was a research trial and sodium citrate spray is not available to purchase, although sodium citrate itself is safe to use and already licensed as a medicine for some stomach and bladder conditions.
For more information on the results of the study visit the UEA website.
For a link to the abstract of the research paper, published in Clinical Otolaryngology, visit the Wylie Online Library