Catamaran 8-K Financial Statements and Exhibits

Exhibit 23.1

Consent of Independent Certified Public Accounting Firm

The Board of Directors

Catamaran Corporation

We hereby consent to the incorporation by reference in the Registration Statements on Form S-3 (No. 333-187011) and Form S-8 (Nos. 333-182598, 333-182569, 333-181189, 333-174671, 333-164021, 333-159733, 333-145450, 333-145449 and 333-136402) of Catamaran Corporation of our report dated March 28, 2013, relating to the financial statements of Restat, LLC which appear in this Current Report on Form 8­K/A of Catamaran Corporation filed with the SEC on November 29, 2013.

/s/ BDO USA, LLP

Milwaukee, Wisconsin

November 29, 2013