GlaxoSmithKline, the British drug giant, has agreed to pay $750 million to settle criminal and civil complaints that the company for years knowingly sold contaminated baby ointment and an ineffective antidepressant - the latest in a growing number of whistle-blower lawsuits that drug makers have settled with multimillion dollar fines.

Altogether, GlaxoSmithKline sold 20 drugs with questionable safety that were made at a huge plant in Puerto Rico that for years was rife with contamination.

Cheryl D. Eckard, the company's quality manager, asserted in her whistle-blower lawsuit that she had warned Glaxo of the problems but the company fired her instead of addressing them. Among the drugs involved were Paxil, an antidepressant; Bactroban, an ointment; Avandia, a troubled diabetes drug; Coreg, a heart drug; and Tagamet, an acid reflux drug. No patients were known to have been sickened, although such cases would be difficult to trace.

In a rising wave, recent lawsuits have asserted that drug makers misled patients and defrauded federal and state governments that, through Medicare and Medicaid, pay for much of health care.

Using claims from industry insiders, federal prosecutors are not only demanding record fines but are hinting at more severe actions.

Justice Department officials announced the settlement in a news conference Tuesday afternoon in Boston, saying a $150 million payment to settle criminal charges was the largest such payment ever by a manufacturer of adulterated drugs. The outcome also provides $600 million in civil penalties. The share to the whistle-blower will be $96 million, one of the highest such awards in a health care fraud.