The Government is being urged to give tax breaks to firms to help tackle a "chronic" sickness absence problem.
The EEF manufacturers' group said tax breaks would encourage employers to pay for private treatment and ease the burden on the NHS.
A survey of more than 300 manufacturers found that two fifths reported that long-term absence has increased in the past two years.
Employer confidence in GPs to improve return-to-work rates has deteriorated, the poll found.
Terry Woolmer, head of health and safety policy at EEF said: "Keeping people fit and healthy, whilst enabling a speedy return to work from absence, is essential to economic growth and improvements in productivity.
"However, currently we have long-term absence on the increase and an under-pressure NHS which is struggling to deal with the issue. Given this situation is only going to get worse with an ageing population, radical action is now required.
"Government must now use fiscal incentives to encourage employers to pay for private medical treatment and allow it to be offset in the same way as other business expenses.
"Not only would this help take the pressure off the NHS but it would allow a speedier return to work. This would be a win win for Government, the employee and employers."