Pick an allergen below to see which other foods commonly cross-react with it in dogs, and what the peer-reviewed veterinary literature says about each pairing. Reaction rates are case-series ranges — your vet's read on your individual dog's history is what matters for treatment decisions.
Gluten cross-reacts with barley and rye; oats variable.
Mechanism: Gluten and prolamin proteins are conserved across wheat, barley and rye (Triticeae tribe of grasses).
Owner note: Wheat-allergic dogs often need to avoid barley as well. Many dog foods labelled "wheat-free" still contain barley.
Source: Olivry et al., 2015
Mechanism: Shared gluten/prolamin proteins with wheat, slightly less common in dog food but present in some bakery-style treats.
Owner note: Less common in commercial UK dog food. Check ingredient labels on supplements and treats.
Source: Olivry et al., 2015
Mechanism: Oats are botanically distinct (Avena genus) and most contain only avenin — but cross-contamination during milling is common.
Owner note: Pure oats are typically tolerated by wheat-allergic dogs, but commercial oat products may be cross-contaminated. Look for "certified gluten-free" labelling if your vet supports oats during the trial.
Source: Veterinary dermatology consensus
Upload a photo of any pet food label and the free scanner flags wheat and the proteins that commonly cross-react with it.
Try free scanThe cross-reactivity rates shown here are case-series figures synthesised from peer-reviewed veterinary dermatology literature. They are population averages — individual dogs can fall well outside the reported range. Vets typically use cross-reactivity data to guide which proteins to exclude during an elimination diet, not as a reason to avoid a protein the dog has tolerated for years without symptoms.
The strongest pairings (high overlap) are the ones to flag with your vet first. The lower-overlap pairings often produce the most successful "novel protein" substitutions — but always confirm the dog has not previously been exposed before starting a trial.
For the long-form context behind these decisions, see the complete elimination diet protocol and the novel-protein vs hydrolysed comparison.
Disclaimer: this tool is education for pet owners, not veterinary advice. Cross-reactivity rates vary by dog, population and methodology. Always confirm specific cross-reactivity decisions for your dog with your vet.