Home Ingredients DAOgest® (Porcine Kidney Diamine Oxidase - Bioiberica)
Gut Health

DAOgest® (Porcine Kidney Diamine Oxidase - Bioiberica)

Evidence Level
Preliminary
1 Clinical Trial
3 Documented Benefits
1/5 Evidence Score

DAOgest® is a branded diamine oxidase (DAO) ingredient from Bioiberica, purified from porcine (pig) kidney, the traditional and most-studied source of supplemental DAO. It is the active enzyme in several consumer DAO products and is designed to survive into the small intestine and break down histamine from food. Like all oral DAO, it is taken just before histamine-rich meals and acts only in the digestive tract, to help people who are sensitive to histamine-containing foods. The published randomized trials of oral DAO used porcine-kidney enzyme, the same source class as DAOgest, and they either did not show a clear benefit over placebo on their main measure (migraine) or showed one only in a low-DAO subgroup (chronic hives); the studies are small, histamine intolerance remains a debated diagnosis, and a 2021 German-Swiss-Austrian allergy guideline does not recommend DAO supplements. No efficacy trial of the DAOgest brand specifically has been published (a 2024 safety study in healthy volunteers is a preprint), so brand-level evidence is preliminary.

Studied Dose 4.2 mg porcine kidney extract (typically labeled 30,000 HDU) per capsule, 15 to 20 minutes before meals, up to three times a day (12.6 mg a day, the EU maximum). Porcine-kidney DAO trials used 4.2 mg tablets; HDU figures are not standardized between brands.
Active Compound Diamine oxidase (DAO) purified from porcine kidney; potency labeled in histamine-degrading units (HDU).

Benefits

Breaks down histamine from food in the gut

DAOgest is purified porcine-kidney DAO, the same enzyme source used in the published DAO trials. Taken before a meal, it is intended to break down some histamine from histamine-rich foods in the gut before it is absorbed; whether enough active enzyme reaches the small intestine has not been shown in people.

Supported by Trial 1

The most-studied DAO source

Porcine-kidney DAO is the form used in the randomized trials in migraine and hives, so a porcine ingredient like DAOgest is backed by more human data at the source-class level than newer plant sources, even though DAOgest itself has not been trialed by brand.

Supported by Trial 1

Purified and potency-standardized

DAOgest is sold with a stated enzyme activity per serving, and the EU novel-food specification for pig-kidney protein extract sets an activity range, which whole desiccated-kidney organ supplements do not have. Finished-product potency is rarely checked independently, and one academic lab found no DAO activity in a commercial pig-kidney capsule (not identified as DAOgest).

Supported by Trial 1

Mechanism of action

1

Oxidative breakdown of dietary histamine

Porcine DAO catalyzes the same reaction as human DAO, removing the amino group from histamine in the gut lumen so that less food histamine is absorbed. It is taken right before meals so the enzyme is present with the histamine load.

2

Works in the gut, not the bloodstream

As a swallowed protein it is not absorbed intact in meaningful amounts and acts on histamine within the digestive tract; it does not lower circulating histamine or replace antihistamine medicines.

Clinical trials

1
Porcine DAO trials (source-class, not the DAOgest brand)
PubMed

Randomized trials of porcine-kidney DAO before meals, e.g. migraine with DAO deficiency (Izquierdo-Casas J, et al. 2019, Clin Nutr 38(1):152-158, PMID 29475774) and chronic urticaria (Yacoub MR, et al. 2018, Int Arch Allergy Immunol, PMID 29698966).

Adults with migraine and low DAO activity, or with chronic spontaneous urticaria; DAOgest itself was not the tested product.

In DAO-deficient migraine, attacks shortened on DAO but not significantly more than on placebo; in a hives crossover with 20 completers, scores improved versus placebo only in patients with low serum DAO. These are source-class data; no published trial has tested the DAOgest brand for efficacy.

Side effects and drug interactions

Common Potential side effects

Made from pig kidney: not vegan, halal, or kosher, and unsuitable for people avoiding pork.
Generally well tolerated; mild digestive symptoms are the most common complaint.
Acts only on histamine from food in the gut; it does not treat allergy or replace antihistamines.
Histamine intolerance is difficult to diagnose; see a clinician before self-treating.

Important Drug interactions

Some medicines inhibit DAO in laboratory tests (for example clavulanic acid, verapamil, metoclopramide); a 2021 allergy guideline calls the data inconsistent. Do not stop a prescribed medicine; ask your pharmacist. Formal interaction studies of oral DAO are lacking. Alcohol may also slow histamine breakdown.
Take before meals as directed; no interactions with the swallowed enzyme itself are established.

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Frequently asked questions about DAOgest® (Porcine Kidney Diamine Oxidase - Bioiberica)

What is DAOgest?

DAOgest® is a branded diamine oxidase (DAO) ingredient from Bioiberica, purified from porcine (pig) kidney, the traditional and most-studied source of supplemental DAO. It is the active enzyme in several consumer DAO products and is designed to survive into the small intestine and break down histamine from food.

What is DAOgest used for?

DAOgest is researched primarily for Gut Health. DAOgest is purified porcine-kidney DAO, the same enzyme source used in the published DAO trials. Taken before a meal, it is intended to break down some histamine from histamine-rich foods in the gut before it is absorbed; whether enough act…

What is the recommended dosage of DAOgest?

The clinically studied dose is 4.2 mg porcine kidney extract (typically labeled 30,000 HDU) per capsule, 15 to 20 minutes before meals, up to three times a day (12.6 mg a day, the EU maximum). Porcine-kidney DAO trials used 4.2 mg tablets; HDU figures are not standardized between brands. Always follow the product label and check with a healthcare provider for personal advice.

Is DAOgest safe, and does it have side effects?

Side effects and cautions reported for DAOgest include: Made from pig kidney: not vegan, halal, or kosher, and unsuitable for people avoiding pork. Generally well tolerated; mild digestive symptoms are the most common complaint. It may also interact with some medications. DAOgest is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does DAOgest interact with any medications?

Possible interactions include: Some medicines inhibit DAO in laboratory tests (for example clavulanic acid, verapamil, metoclopramide); a 2021 allergy guideline calls the data inconsistent. Do not stop a prescribed medicine; ask your pharmacist. Formal interaction studies of oral DAO are lacking. If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for DAOgest?

NutraSmarts rates the evidence for DAOgest as Preliminary (1 out of 5). It is backed by 1 study summary and 2 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(2 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Izquierdo-Casas J, Comas-Basté O, Latorre-Moratalla ML, Lorente-Gascón M, Duelo A, Soler-Singla L, Vidal-Carou MC. Diamine oxidase (DAO) supplement reduces headache in episodic migraine patients with DAO deficiency: A randomized double-blind trial. Clinical Nutrition. 2019;38(1):152-158. doi:10.1016/j.clnu.2018.01.013.PubMedUsed to support: Randomized double-blind trial of porcine-kidney DAO (the same source class as DAOgest) in 100 people with DAO-deficient migraine: attack duration fell within the DAO group (6.14 to 4.76 hours), but placebo also improved and the difference between groups was not significant. Source-class evidence; not a trial of the DAOgest brand.
  2. Yacoub MR, Ramirez GA, Berti A, Mercurio G, Breda D, Saporiti N, Burastero S, Dagna L, Colombo G. Diamine Oxidase Supplementation in Chronic Spontaneous Urticaria: A Randomized, Double-Blind Placebo-Controlled Study. International Archives of Allergy and Immunology. 2018;176(3-4):268-271. doi:10.1159/000488142.PubMedUsed to support: Randomized placebo-controlled crossover trial of porcine DAO added to antihistamines in chronic urticaria (20 completers): UAS-7 scores improved versus placebo only in patients with low baseline serum DAO (p=0.041), and antihistamine use fell slightly. Source-class support for porcine DAO; not a trial of DAOgest specifically.