Updated from 2:17 p.m. EDT Shares of Taro Pharmaceutical Industries ( TARO) were among the worst-performing health and pharmaceutical stocks Thursday after the company posted a second-quarter loss and weaker-than-expected sales. The pharmaceutical company lost 31 cents a share on sales of $49.1 million. Analysts polled by Thomson First Call had expected it to post a profit of 44 cents a share on sales of $88.5 million. The company blamed the sales shortfall on reduced purchases by several of its customers and competitive pricing pressure. Shares of Taro Pharmaceutical Industries traded down $5.94, or 19.8%, to $24.14. AMN Healthcare Services ( AHS) fell after it posted weaker-than-expected second-quarter financial results and warned that third-quarter results would be below expectations. The health care staffing company earned 14 cents a share during the second quarter on sales of $153.4 million. Analysts had expected it to earn 15 cents a share on sales of $159.4 million. Looking ahead, it expects third-quarter earnings of 11 cents to 14 cents a share on sales of $151 million to $157 million. Analysts were expecting earnings of 17 cents a share on sales of $164.8 million. Shares of AMN Healthcare traded down 77 cents, or 5.4%, to $13.39. Shares of Nutraceutical International ( NUTR) fell after the company reported weaker-than-expected third-quarter results that fell far short of expectations. The nutritional supplements company earned 24 cents a share on sales of $33.8 million. Analysts had expected it to earn 36 cents a share on sales of $38.3 million. The quarter's results were impacted by higher costs in shipping, insurance, legal and corporate governance. Shares of Nutraceutical International traded down $4.67, or 26.4%, to $13. Advancis Pharmaceuticals ( AVNC) fell after it reported weaker-than-expected second-quarter earnings and sales and warned that its full-year results would fall short of expectations. The pharmaceutical company posted a loss of 37 cents a share on sales of $900,000. Analysts had expected it to post a loss of 35 cents a share on sales of $3.1 million. Looking ahead, Advancis forecast a full-year loss of $1.50 to $1.75 a share on sales of between $15 million and $20 million. Analysts were looking for a loss of $1.15 a share on sales of $21 million. Shares of Advancis Pharmaceuticals traded down 86 cents, or 9.6%, to $8.10.