CVS Health missed first-quarter expectations and chopped its 2024 outlook more than a dollar below Wall Street's forecast.

Shares of the health care giant plunged Wednesday morning after the company said it was still struggling with rising costs from care use in its Medicare Advantage business.

Medicare Advantage plans are privately run versions of the federal government's Medicare program for people age 65 and older.

CVS Health said it now expects adjusted earnings to be at least $7, down its previous forecast of at least $8.30.

For the full year, analysts expect earnings of $8.27 per share, according to FactSet.

The guidance reduction was much more significant than expected, according to Leerink analyst Michael Cherny. He said in a research note that it raises questions about the company's path to reaching its previously stated goal of double-digit growth in earnings per share next year.

In the first quarter, CVS Health booked adjusted earnings of $1.31 per share on total revenue of $88.4 billion.

Analysts expected earnings of $1.69 per share on $89.33 billion in revenue for the first quarter, according to FactSet.

CVS Health Corp. runs one of the nation's largest drugstore chains and a huge pharmacy benefit management business that operates prescription drug coverage for big clients like insurers and employers. It also sells health insurance through its Aetna arm.

Shares of the Woonsocket, Rhode Island-based company were down 11% to $60 in premarket trading.