Older people who are cocooning face a long-term impact on their physical and mental wellbeing, according to Alone.
The charity says it has also received nearly 19,000 calls to a special phoneline set up at the start of the pandemic.
Alone chief executive Sean Moynihan says there has been an increase in calls in the last few days about non-Covid hospital visits.
"The big surge in work this week for the people that we support and the people coming through on the phonelines has been health issues," said Mr Moynihan.
"People needing access to GP services, some people in poor housing conditions, some people for chiropody and some people very de-conditioned and very worried about falls because they have been cocooning for so long."
Mr Moynihan said that the fear of falls is because people are not as confident or steady on their feet as they were.
"We are advising people around health and wellbeing, creating a purpose for your day but also on top of that is we are making sure that people are engaged with hospitals, primary care.
"The big thing is making sure that people have all the medication they need and making sure they are keeping up with prescriptions and adhering to them."