Officials removed Comtrex cold capsules from stores in the Roanoke area after small amounts of rat poison were found in two bottles of the remedy, the Virginia pharmacy director said yesterday. They said the small amount of poison found would not have been harmful.

Jack Carson, executive director of the Virginia State Board of Pharmacy, said the poison was found in bottles obtained from a Revco Discount Drug Center. The active ingredient in rat poison is warfarin, and a large amount is required for a lethal dose, Carson said.

He said the incident is believed to be an isolated one involving only the single store. State and federal officials confiscated hundreds of bottles of Comtrex from other stores for testing. Preliminary results show no other bottles were tampered with, Carson said, adding that Comtrex was not removed from sale.

Harry Levine, spokesman for Bristol-Myers Co. in New York, which makes Comtrex, said the company was informed that the Roanoke case was "an isolated criminal incident."

Thomas Hooker, regional director of the U.S. Food and Drug Administration in Baltimore, said the agency was informed of the tampering Thursday after a woman said she became ill. Her condition never was serious, authorities said.