Cancer patients commonly experience depression and fatigue before, during, and after treatment. Symptoms can be debilitating, and the risks associated with unrecognized or inadequately treated depression are substantial. Inflammation may be important in the genesis of depression and fatigue in cancer patients; potential neurobiological mechanisms of inflammation-related behavioral symptoms are reviewed. Randomized studies of pharmacologic treatments for depression in cancer populations are limited, but available data are generally encouraging. Studies of pharmacologic treatments for cancer-related fatigue have been more numerous but with mixed results. A practical approach to pharmacologic treatment of depression and fatigue in cancer patients involves weighing the potential risks and benefits of specific agents, including potential for adverse or advantageous side effects. Progress in understanding the neurobiological mechanisms underlying inflammation-related behavioral symptoms will provide opportunities for the development of novel and targeted treatments.