Two of the nation’s largest drug companies--Schering-Plough...

Two of the nation’s largest drug companies--Schering-Plough and Sterling Drug--reported healthy increases in second-quarter earnings, but SmithKline Beckman said a nationwide drug-tampering scare cut into its profit. Schering-Plough, based in Madison, N.J., attributed the 30% increase in its second-quarter profit to gains by its U.S. pharmaceutical business. New York-based Sterling Drug, meanwhile, said its profit for the period ended June 30 rose 10% to $36.6 million. Sterling Chairman John M. Pietruski said sales of the company’s domestic health-care businesses and non-U.S. operations showed strong gains. Although SmithKline Beckman of Philadelphia reported a 14.5% rise in second-quarter sales, its net earnings inched up only 1.6%, largely because of the costs of re-introducing Contac cold medicine. Contac was taken off the market in March after a tampering incident.