The company's chief executive said that the company would suffer from slowing prescription sales.
Shares of CVS fell 11%.
The 2017 projections soured what might have been an otherwise decent third-quarter earnings report.
For the quarter, CVS soundly beat a few of the analyst expectations.
Earnings clocked in at $1.64 a share, versus the consensus estimate of $1.57 a share. Net income attributable to CVS's pharmacies rose by 24% year over year, to $1.54 billion or $1.43 a share, from $1.25 billion, or $1.11 a share.
To be sure, revenue of $44.6 billion was below analysts' forecasts.
But that's not the biggest disappointment to come out of Tuesday's earnings announcement.
For fiscal 2017, CVS announced that it expects adjusted earnings to range from $5.77 to $5.93 per share. That is far from the $6.53 per share that the Wall Street consensus forecast. And the company further displeased investors by announcing a "multiyear" plan to buy back another $15 billion of its own stock.
Part of the company's expected woes next year is attributable to restrictive changes to pharmacy networks. "Very recent pharmacy network changes in the marketplace are expected to cause some retail prescriptions to begin migrating out of our pharmacies this quarter," said CVS CEO Larry Merlo on Tuesday. "In addition, we are currently experiencing slowing prescription growth in the overall market as well as a soft seasonal business."