Express Scripts Holding Co. shares tumbled Wednesday, a day after the pharmacy benefits manager lowered its 2014 forecast, disappointed Wall Street with its first-quarter report and said it received a handful of subpoenas tied to government inquiries.

The nation's largest pharmacy benefits manager said Tuesday after markets closed that severe winter affected its prescription sales during a first-quarter in which earnings dropped 12 percent.

Express Scripts also cut its 2014 earnings guidance to between $4.82 and $4.94 per share, citing several customer delays which pushed back implementation of service to early 2015 from mid-2014. The company had previously forecast earnings in the range of $4.88 to $5 per share.

Chairman and CEO George Paz told analysts during a Wednesday morning conference call that he "absolutely" feels comfortable with the new forecast.

Pharmacy benefits managers, or PBMs, run prescription drug plans for employers, insurers and other customers. They process mail-order prescriptions and handle bills for prescriptions filled at retail pharmacies.

The St. Louis company said Tuesday that it earned $328 million, or 42 cents per share, in the three months that ended March 31. That was down from $373 million, or 45 cents per share, in last year's quarter. Adjusted profit was 99 cents per share. Revenue fell 8.8 percent to $23.68 billion.

Analysts forecast, on average, earnings of $1.01 per share on about $23.83 billion in revenue.

Express Scripts also disclosed Tuesday in a quarterly filing with the Securities and Exchange Commission that it has received a subpoena in each of the last three months on separate issues.

The first came in late February from the U.S. Department of Justice, District of Rhode Island, and asks for information about the PBM's relationship with Pfizer Inc. and other drugmakers. The next arrived late last month from the New Jersey attorney general and the third came in April from the U.S. Department of Labor, Employee Benefits Security Administration.

Express Scripts said in the filing that it intends to cooperate with all the inquiries.

The company also said Tuesday that it expects second-quarter adjusted earnings to a range between $1.20 to $1.24 per share.

That falls short of average analyst expectations for $1.26 per share, according to FactSet.

Express Scripts shares started falling Tuesday after the earnings report came out. On Wednesday afternoon, the stock was down about 5 percent, or $3.66, to 67.36 while broader indexes were largely flat.