Ian Megahy, from Hamilton, South Lanarkshire, will appear before the Welfare Reform Committee as part of its Your Say appeal for testimony on the impact of the Department for Work and Pensions' (DWP) benefit reforms.
Last week, the DWP revealed that more than a quarter of Scots on incapacity benefit prior to October 2010 had now been reclassified as "fit for work" – in excess of 17,000 people.
But those giving evidence to the committee believe the DWP and its private-sector assessors, Atos Healthcare, are not listening to the fears of genuinely disabled people.
Mr Megahy, a former veterinary surgeon with chronic pain condition fibromyalgia, was reclassified "fit for work" after eight years on incapacity benefit.
He said he was sent home from his Atos assessment in a courtesy taxi after being deemed too sick to travel from Glasgow to Hamilton by public transport, and later collapsed after being told his appeal had failed.
"The diagnosis was a severe flare-up of my condition caused by stress and I believe the call from the DWP was a major factor," he wrote to the committee.
"My condition has continued to deteriorate in that I have begun to use a wheelchair."
Mr Megahy will be joined by former teacher Marlene Hepburn, from Stirling, who believes the reform agenda is worsening her multiple sclerosis .
Ms Hepburn was reclassified fit for work after five years on incapacity benefit. She said: "I appreciate the system needs to be reformed, but not to the detriment of genuine claimants."
Committee convener Michael McMahon, a Labour MSP, said: "It is easy for talk of welfare reform to be about numbers or to generalise. The reality is it affects individuals."
A DWP spokeswoman said: "The previous system abandoned people to life on benefits without checking to see if they could, with the right support, go back to work."