High-quality information about palliative and end-of-life care is limited. In addition, much of what has been studied has focused on cancer. Studies in patients with cancer may not always apply to patients who are near the end of life because of other types of illness, such as heart disease, lung disease, or dementia. The authors also found that it is difficult to predict the best timing for palliative care, so doctors and patients need to make decisions about the timing of how to incorporate these approaches in their medical treatment on a case-by-case basis. Studies support the use of anti-inflammatory drugs, narcotics, and bisphosphonate drugs for pain due to cancer. Some of these treatments work only in specific patients. For example, radiation treatment is especially helpful when cancer causes bone pain. Studies also show that narcotics and oxygen can lessen the discomfort of the shortness of breath experienced by many patients with advanced lung disease. Antidepressant drugs and psychological treatments improve symptoms of depression in patients with cancer. Although strong studies are not available, some recent studies show how advance care planning can be helpful in improving the end-of-life experience for seriously ill patients.