Ornithine ketoglutarate (OKG) is an amino acid salt composed of ornithine and alpha-ketoglutarate. It has been investigated as a nutritional supplement in the management of debility—particularly in clinical settings involving malnutrition, muscle wasting, or prolonged illness.

The rationale for its use is primarily based on its potential to support protein synthesis, reduce protein catabolism, and enhance wound healing. Several studies, particularly in the 1980s and 1990s, explored OKG supplementation in elderly patients, burn victims, and those with chronic illness. Clinical trials have shown that OKG can stimulate the secretion of anabolic hormones (such as insulin and growth hormone), which may help preserve lean body mass and promote recovery in debilitated patients. For example, studies in hospitalized elderly patients and those recovering from surgery have reported improvements in nitrogen balance and, in some cases, functional outcomes such as muscle strength.

However, while some evidence supports its efficacy, results are mixed, and most studies are small or methodologically limited. Meta-analyses and systematic reviews suggest modest benefits for specific populations (e.g., elderly, post-surgical, or critically ill patients), but large, high-quality randomized controlled trials are lacking. Thus, the scientific evidence is suggestive but not definitive, supporting a moderate rating.

OKG is not widely used outside clinical nutrition settings, and its use is generally adjunctive rather than primary therapy for debility.