A new study will consider whether vitamin A can help those who have lost their sense of smell after having Covid-19.
The 12-week ‘Apollo trial’ will treat people who have experienced smell loss or an altered sense of smell as a result of viral infections with nasal drops containing the vitamin, the University of East Anglia (UEA) in England said in a statement.
The university said research from Germany had shown the potential benefit of the vitamin, and its team “will explore how this treatment works to help repair tissues in the nose damaged by viruses”.
The researchers hope the study “could one day help improve the lives of millions around the world who suffer from smell loss, by returning their fifth sense”.
It comes after a study by an international group of smell experts, published in the journal International Forum of Allergy & Rhinology in April, advised against using steroids to treat smell loss and instead suggested “smell training”.
One of the researchers, Prof Carl Philpott from UEA’s Norwich Medical School, said there was “very little evidence” steroids will help with smell loss and they have “potential side effects including fluid retention, high blood pressure, and problems with mood swings and behaviour”.
Four odours, twice daily
Instead, the scientists recommended those who have experienced smell loss sniff at least four different odours, twice daily for several months.
Prof Philpott said the method “aims to help recovery based on neuroplasticity – the brain’s ability to reorganise itself to compensate for a change or injury”.
Those interested in participating in the university’s vitamin A study are asked to seek a referral from their GP to the Smell and Taste Clinic at the James Paget Hospital in Norfolk’s Great Yarmouth.
The study, which is being funded by the UK's National Institute for Health Research, will begin recruiting participants in December.
