A widely available and inexpensive drug that is used to relieve symptoms of indigestion may prove a worthy contender for treating COVID-19 infection in those whose illness does not require hospitalization, suggest the results of a small series of cases published in the journal Gut.
These effects were felt within 24 to 48 hours of taking famotidine, and a thorough clinical trial is now required to understand whether the drug can be an effective treatment for COVID-19, the researchers say.
Famotidine belongs to a class of drugs known as histamine-2 receptor antagonists, which reduce the amount of gastric acid produced. Famotidine can be taken in doses of 20-160 mg, up to four times a day, for the treatment of acid reflux and heartburn.
Researchers report 10 people (6 men and 4 women) who developed COVID-19 infection, and all of them took famotidine during their illness.
The severity of the five main symptoms-cough, shortness of breath, fatigue, headache and loss of taste / smell, as well as general malaise—was measured using a 4-point scale commonly used to assess the severity of cancer symptoms (ECOG PS).
Seven patients tested positive for COVID-19 using a smear test; two had antibodies to the infection; and one patient was not tested but was diagnosed with the infection by a doctor.
Their ages ranged from 23 to 71, and they had a diverse ethnic background and known risk factors for the severity of COVID-19, including high blood pressure and obesity.
The most commonly used dose was 80 mg, taken three times a day, with an average treatment period of 11 days, but varying from 5 to 21 days.
All 10 patients said symptoms improved rapidly within 24 to 48 hours of starting famotidine and mostly disappeared after 14 days.
The improvement was evident in all the assessed symptom categories, but respiratory symptoms such as coughing and shortness of breath improved faster than systemic symptoms such as fatigue.
Seven patients did not experience any side effects while taking famotidine, and three of them were mild, and all but temporary forgetfulness were known side effects associated with taking the drug.
Despite the promising results, the researchers note that the results of the study may have been influenced by the “placebo effect“.
“Our case series suggests but does not establish the benefit of famotidine treatment in outpatient patients with COVID-19,” they warn. And it’s unclear how Famotidine might work: whether it could somehow disable the virus or change a person’s immune response to it
However, they suggest that their results warrant further more detailed study, adding that a clinical trial testing the combination of famotidine with the antimalarial drug hydroxychloroquine in patients admitted to the hospital with COVID-19 is already underway.