I believe you need to e-prescribe a minimum of 10 times during patient encounters before June 30, 2011 to avoid the penalty.
The bill submitted to medicare has to include a special item that indicates that at least one rx was generated electronically during that visit. It's a special G-code, that should not be charged ($0.00).
See:
http://www.cms.gov/ERxIncentive/Downloads/2011eRxIncentiveProgramUpdatefor2012PaymentAdjustment.pdfand
http://www.cms.gov/erxincentive/and
http://www.cms.gov/ERxIncentive/Downloads/2011_eRx_ClaimsBasedReportingPrinciples_111510.pdffor more information.
I'm just starting doing this, so please, correct me if I'm wrong, somebody.
Michael J
New York