FDA warning letters are issued by the FDA to manufacturer when a violation of FDA regulation has occurred. The letter states the violation and provides direction and timeframe for the correction. Companies with records of warning letters could be least reliable in producing good quality products and more prone for future recalls. For scoring, 10 points are given to suppliers without warning letters and 0 points to those that had warning letters. From the FDA websites, 4 warning letters have been given to 4 different suppliers of hydrocodone acetaminophen. However, those suppliers have all discontinued their production. Therefore, records of warning letters are not a good element to rank existing suppliers in the case of hydrocodone acetaminophen. All the suppliers from our list have receive 10 points for this