Cachexia and sarcopenia present several analogies in both the pathogenic mechanisms and the clinical picture. The loss of muscle mass and strength is a hallmark of these two clinical conditions. Although frequently overlapping and often indistinguishable, especially in old individuals, these two conditions should be considered distinct clinical entities. A prompt and accurate patient evaluation, guiding the physician through a proper differential diagnostic procedure and providing the best therapeutic options, is recommended. Given the several commonalities between cachexia and sarcopenia, it is likely that the therapeutic approaches may prove effective in both conditions. This review focuses on the most recent available literature and aims at providing physicians with the correct tools that are available to aid in diagnosing these two different entities that often clinically overlap. Currently available or proposed therapeutic strategies for pre-cachexia, cachexia and sarcopenia are also briefly described.