Even if an employee has exhausted their FMLA leave for the year, their condition may fall under the Americans with Disabilities Act (ADA). Under the ADA, a disabled employee is one who has a physical or mental impairment that substantially limits one or more major life activities such as seeing, hearing, speaking, walking, performing manual tasks, and working. If the employee’s condition is covered by the ADA, they would be entitled to continued job protection while on a leave of absence, so long as their leave did not create an undue hardship for the company.
If the employee contacts you about needing an extension of the leave, you should engage in the ADA interactive process to determine if their condition makes them eligible for ADA leave and how much additional time they would need before returning. As part of the interactive process, you may request medical documentation supporting an accommodation request. You can then look at whether the additional leave is something you can grant without it causing an undue hardship. Be aware, however, that “undue hardship” is a high bar to pass.
You could also choose to offer additional leave to an employee even if their condition did not require coverage under the ADA (employers occasionally want to do this with top performers). But keep in mind that doing this would set a precedent for future requests, so it should be carefully considered.