Which of the following is an example of an opioid?

Vicodin is considered an opioid because it contains hydrocodone, which is a semi-synthetic opioid pain medication. Opioids work by binding to specific receptors in the brain and spinal cord, which helps to reduce the perception of pain. Vicodin is often prescribed for the management of moderate to severe pain and is known for its effectiveness in providing relief.

The other options listed are not classified as opioids. Ibuprofen and aspirin belong to a group of medications known as non-steroidal anti-inflammatory drugs (NSAIDs), which relieve pain and reduce inflammation through a different mechanism that does not involve opioid receptors. Acetaminophen, commonly known as Tylenol, works as a pain reliever and fever reducer but is also not an opioid. It has distinct action pathways that do not include the opioid receptor system. Therefore, Vicodin stands out as the correct example of an opioid medication.