Not so fast. While most federal student loans are eligible to be discharged on account of disability, private and state loan programs may not be.

For those who are expected to be unable to work for at least five years, the federal student loan program has what's called a "total and permanent disability" (TPD) discharge. Generally, those who are granted a discharge get their loans cancelled permanently.

A TDP discharge is eligible for loans from the Federal Direct Loan Program, Perkins Loans, and the Federal Family Education Loan (FFEL) Program. Additionally, service obligations for the Teacher Education Assistance for College and Higher Education (TEACH) grant program can be cancelled.

TPD discharges are also granted for veterans with 100% service-connected disabilities and for those whose disabilities are expected to result in death.

Note that the fact that the Social Security Administration has already recognized that you're unable to work doesn't guarantee that the Department of Education will forgive your loan; the TPD discharge requirements are harder to meet then Social Security's.

To apply for a TPD discharge, go to disabilitydischarge.com and fill out a Discharge Application: Total and Permanent Disability. There is a page of the form that your doctor needs to fill out, providing details of your disability and certifying that you are disabled. You then send the application to your loan servicer.

A couple of important things to note: The IRS may treat the amount of your cancelled loan as income to you, meaning you'll have to pay taxes on it. Also, if, within three years of getting a TPD discharge, you have a significant amount of non-disability income, your discharge may be revoked.

For more information, see Nolo's article on canceling student loans due to disability.