Which medication may be used to alleviate severe pain related to cancer?

Morphine Sulfate is a potent opioid analgesic that is widely recognized for its effectiveness in managing severe pain, particularly in patients suffering from cancer. It works by binding to specific receptors in the brain and spinal cord, leading to a decrease in the perception of pain and an increase in pain tolerance. This medication is often the cornerstone of palliative care for cancer patients, as it addresses not only the intensity of pain but also improves quality of life.

Other medications listed may have roles in pain management or related symptoms, but they are not primarily used for severe pain associated with cancer. For example, Amitriptyline is usually prescribed for chronic pain or depression but is not an effective choice for managing acute or severe pain. Dexamethasone is a corticosteroid that can help reduce inflammation and pain, especially in cases involving swelling, but it does not provide the direct analgesic effects that morphine does. Ibuprofen, a nonsteroidal anti-inflammatory drug (NSAID), is suitable for mild to moderate pain relief but is insufficient for severe pain scenarios, such as those often experienced by cancer patients.

Thus, morphine sulfate stands out as the appropriate choice for alleviating severe cancer pain, making it the correct answer.