Smell training could help Covid patients combat loss of scent

People struggling with their sense of smell after having Covid-19 should undergo “smell training”, researchers say. 

The training would involve sniffing different scents over several months to help the brain recognise the various smells.  

Losing a sense of smell is one of the main symptoms of coronavirus infection, along with a fever and a persistent cough.   

In most cases, it returns relatively quickly once the illness has passed. 

But one in five people report they continue to have problems eight weeks after falling ill. 

Now, scientists believe rather than treating people with steroids a “smell retraining programme” would be cheaper and with no side effects. 

In a paper published in the journal International Forum of Allergy & Rhinology, researchers suggest this treatment. 

This would mean sniffing four things that have a distinctive aroma –  such as oranges, mint, garlic or coffee – twice a day for several months.  

Steroid treatment has been one course of treatment prescribed for smell loss.  

However, Prof Carl Philpott, from the University of East Anglia’s Norwich Medical School, who was part of the team reviewing current evidence, said because steroids have potential adverse side effects “our advice is they should not be prescribed for post-viral smell loss.”  

Steroids’ side effects include fluid retention, high blood pressure, and mood disorders. 

Prof Philpott said most people who experience smell loss because of Covid-19 will regain their sense of smell “spontaneously”.  

Research shows 90 per cent of people fully recover it after six months. 

However, for those who continue to experience smell loss, “smell training” is advised.  

The process helps to retrain the brain’s smell pathways to recognise different scents. 

Professor Philpott said: “It aims to help recovery based on neuroplasticity – the brain’s ability to reorganise itself to compensate for a change or injury.”