A pharmaceutical company says it will plead guilty to selling adulterated and mislabeled generic medicine for high blood pressure.

Bolar Pharmaceutical Co., of New York, also will admit to obstructing a Food and Drug Administration inquiry and lying to investigators.The U.S. attorney claims Bolar substituted brand-name drugs for its own during testing of its hypertension drug, Triamterene-Hydrochlorothiazide. Between approval by the FDA in August 1987 and its withdrawal in January 1990, $140 million of the drug was sold, prosecutors said Tuesday.

"Bolar has chosen to plead guilty . . . because it believes that to do so is in the best interest of the company and its stockholders," the company said in a statement.

The company said it will plead guilty to all 20 charges filed Tuesday and pay $10 million in fines and $250,000 in other costs.

The charges are the latest in a continuing probe of the generic drug industry. Since July 1988, five former FDA employees, five generic drug company executives, one consultant and three generic drug companies have been convicted on charges involving corrupt relationships between individuals in the FDA's Generic Drug Division and industry representatives.