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Limited evidencePhysical performance

OKG (Ornithine Alpha-Ketoglutarate)

An amino acid salt used in hospital nutrition for burns and wounds. Even the clinical evidence is rated uncertain, and there is essentially nothing supporting its use by healthy trainees.

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What the science says

  • Pressure ulcer healing is very uncertain Limited evidence

    The 2024 Cochrane review of nutritional interventions for pressure ulcers examined ornithine alpha-ketoglutarate specifically and concluded the evidence about its effect on ulcer healing is very uncertain.

  • Clinical use in burn patients Limited evidence

    A randomized controlled trial in burn patients compared modes of enteral OKG administration, and a later umbrella review of nutritional interventions in burns found the supporting evidence across such supplements generally low certainty.

  • No evidence in healthy athletes Limited evidence

    No randomized trial supports OKG for strength, lean mass or recovery in healthy trained people, despite its marketing in that category.

Dosage & safety

Studied doseHospital studies used 10–20 g/day by the enteral route. Supplement labels typically suggest 2–5 g/day, a dose with no supporting trials.
SafetyReasonably tolerated in hospital use; gastrointestinal upset is the usual complaint. Avoid in kidney or liver failure without medical supervision, since nitrogen and ammonia handling are impaired in those conditions.

How to take it

TimingTiming does not matter on the evidence available.
With food?With food, which reduces the gastrointestinal upset that is the usual complaint.
Worth knowingCompare the label to 10–20 g/day before buying — a 2 g capsule dose has never been tested against anything.

Frequently asked questions

Does OKG help build muscle or improve recovery?

No randomized trial supports OKG (ornithine alpha-ketoglutarate) for strength, lean mass or recovery in healthy trained people, despite its marketing. The evidence grade is limited.

What is ornithine alpha-ketoglutarate used for?

OKG is used in hospital nutrition for burns and wounds, but even there evidence is limited: a 2024 Cochrane review found its effect on pressure ulcer healing very uncertain, and burn-care evidence is generally low certainty.

How much OKG should I take?

Hospital studies used 10–20 g/day of OKG by the enteral route, while supplement labels typically suggest 2–5 g/day, a dose with no supporting trials. Take OKG with food to reduce gastrointestinal upset.

Is OKG safe?

OKG is reasonably tolerated in hospital use, with gastrointestinal upset the usual complaint. Avoid OKG in kidney or liver failure without medical supervision, since nitrogen and ammonia handling are impaired in those conditions.

Scientific references

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