An antibiotic plagued by serious blood-sugar complications is coming off the market, the Associated Press reports. Bristol-Myers Squibb Co. confirmed recently that it plans to stop making and selling Tequin. Spokesman Eric Miller said the company will return rights to the drug to Kyorin Pharmaceutical Company in Japan. He said the company acted after an evaluation of the product as well as ongoing transition in the company''s focus. Approved for sale in 1999, Tequin has faced questions about its effects on blood sugar, being associated with both high- and low-blood sugar in some patients. In February the Food and Drug Administration required increased warnings on the label of the drug. The manufacturer has warned that it should not be used by diabetics and said the elderly and those with kidney disease are more likely to have problems. Tequin is prescribed for chronic bronchitis, sinusitis, pneumonia, urinary tract and other infections. Tequin had $150 million in global sales last year including $100 million in the U.S.