According to Drugs.com, there are two possibilities for what a pill imprinted with "IP 203" contains. If it is a round, white pill, it contains 325 mg of acetaminophen and 5 mg of oxycodone. If it is a blue and green capsule that also reads "18 mg," it contains Zorvolex.
According to MedicineNet, acetaminophen is a common over-the-counter pain and fever reliever. Oxycodone is a narcotic pain reliever similar to morphine. When the two drugs are combined, they cause much higher pain relief than either taken alone.
Drugs.com lists Zorvolex, or diclofenac, as a non-steroidal anti-inflammatory drug usually taken to relieve the pain and inflammation associated with arthritis and ankylosing spondylitis.