As mentioned earlier, there is no medication known as "Darvocet 500mg." Darvocet was typically a combination medication containing propoxyphene and acetaminophen, with dosage strengths typically ranging from 100mg of propoxyphene napsylate and 500mg of acetaminophen. However, Darvocet has been discontinued due to safety concerns. If you require information on a different medication or dosage, please specify, and I'll be glad to assist you further.