MediKids Health Insurance Act of 2009 - Amends the Social Security Act to add a new title XXII (Medikids Program), which creates a program to guarantee comprehensive health care coverage, including prescription drugs for all children meeting specified age requirements.
Creates the MediKids Trust Fund.
Expands the duties of the Medicaid and CHIP Payment and Access Commission (MACPAC).
Amends the Internal Revenue Code to: (1) impose a MediKids premium for the taxable year, with an exemption for very low-income taxpayers; and (2) create a refundable tax credit providing a catastrophic limit on MediKids cost-sharing expenses.
Directs the Secretary of the Treasury to propose a gradual schedule of progressive tax changes to fund the Medikids program, as the number of enrollees grows in the out-years.