Shares of Sun Pharmaceuticals fell as much as 2.5 per cent in morning trade on Friday.
At about 10.20 am, the shares were down Rs 12.90 or 1.49 per cent at Rs 852.25.
India's largest drug maker has voluntarily recalled 381,120 cartons of osteoporosis drugs in the US and Puerto Rico, according to a note on the US FDA website.
According to FDA, the reason for recall was: "Observed levels of highest unknown impurity exceeding specification limit at the 3 month stability time point.”
The drug was manufactured at Sun Pharma's Halol plant in Gujarat. FDA had warned Sun Pharma over standards at Halol plant in December.