What does Larazotide do? Benefits and evidence

Larazotide is an experimental oral peptide studied for celiac symptoms and post-COVID illness. Some small trials found symptom benefits, but the celiac phase 3 trial stopped in 2022. The completed long-COVID trial has no posted results. Community use for “leaky gut” remains poorly tested. Online products may differ from trial capsules.

• In a celiac trial, 0.5 mg three times a day eased symptoms on top of a gluten-free diet; a later phase 3 trial was stopped. (Studied in a trial)
• In a small study, people with celiac disease had less gut leak and fewer symptoms after eating gluten. (Studied in a trial)
• In a small trial of 12 children with MIS-C, a post-COVID illness, recovery was faster when it was added to hospital care. (Studied in a trial)
• A few users report fewer food reactions or better food tolerance; another noticed no benefit. (Reported by users)

Uses in the sources

• Studied as an add-on to a gluten-free diet for persistent celiac symptoms. Benefit was inconsistent across doses and trials. (Studied in a trial) (source)
• Studied as an add-on to hospital care for MIS-C. A 12-child trial reported faster recovery; it does not establish routine use. (Studied in a trial) (source)
• Studied for long COVID in 107 participants aged 7–50. The trial is completed; results were not posted by 2026-10-18. (Studied in a trial) (source)
• People report oral use for “leaky gut,” food reactions, MCAS and chronic gut symptoms. These reports do not establish benefit. (Reported by users) (source)