Common side effects These may affect up to 1 in 10 people: • Feeling sick or being sick (nausea or vomiting), pain in the stomach, loose stools • Skin rashes (red, raised or itchy) – if the skin rash is severe, you may have to stop taking this medicine • Headache, feeling dizzy • Feeling tired • Increases in enzymes produced by the liver called transaminases, increases of an enzyme produced by the pancreas called lipase.