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Review

Food Allergy in Companion Animals: Integrating Traditional Diagnostics with Emerging Approaches

by
Daniela Matias
1,2,* and
Luís Martins
1,3
1
MED—Mediterranean Institute for Agriculture, Environment and Development & CHANGE-Global Change and Sustainability Institute, University of Évora, Polo da Mitra, Ap. 94, 7006-554 Évora, Portugal
2
IIFA—Institute for Advanced Studies and Research, University of Évora, Polo da Mitra, Ap. 94, 7006-554 Évora, Portugal
3
Department of Veterinary Medicine, School of Sciences and Technology, University of Évora, Polo da Mitra, Ap. 94, 7006-554 Évora, Portugal
*
Author to whom correspondence should be addressed.
Appl. Sci. 2026, 16(5), 2169; https://doi.org/10.3390/app16052169
Submission received: 28 November 2025 / Revised: 10 January 2026 / Accepted: 13 January 2026 / Published: 24 February 2026
(This article belongs to the Section Applied Biosciences and Bioengineering)
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Versions Notes

Abstract

Food allergy is an exaggerated immune response, mediated by Immunoglobulin E (IgE) or by cells, to food antigens. Dogs and cats may present with both dermatological and gastrointestinal manifestations, although non-seasonal pruritus is the most common clinical sign. Despite advances in understanding the immunopathogenesis of this condition, the elimination–provocation test remains the gold standard for diagnosis. However, new diagnostic approaches, like molecular allergen macroarrays and lymphocyte proliferation assays, may complement traditional strategies, opening new perspectives for accurate diagnosis. For long-term management, strict avoidance of offending allergens is essential, but emerging therapeutic interventions, including immunotherapy using food components and targeted modulation of the gut–skin axis, are promising for improving clinical outcomes. This review summarizes current knowledge and highlights innovative approaches that can transform the diagnosis and management of food allergy in companion animals.

1. Introduction

Food allergy is an exaggerated immune response to food antigens [1,2] and may occur by both a type I (IgE-mediated) or a type IV (cell-mediated) hypersensitivity reaction [1,3]. However, some controversy regarding the nomenclature for this condition may arise as some authors refer to “food allergy” as an “adverse food reaction”. In fact, the latter term encompasses food allergy, an immunological event, but also food intolerance, a toxic/pharmacological/idiosyncratic reaction to food [3]. Hence, considering that cutaneous adverse food reactions described in dogs and cats appear to have an essentially immunological basis, we have chosen to use the term “food allergy” in this review.
The prevalence of food allergy in dogs and cats is less than 1% but represents 10 to 25% of allergic skin diseases in companion animals [4] and affects all ages and genders, in both canine and feline species [5]. There is no clear racial predisposition, but more than 1/3 of the dogs with food allergy are represented by four breeds: German Shepherd, Labrador, Golden Retriever and West Highland White Terrier [5]. Some studies have suggested an increased risk in Siamese and Siamese-cross cats, but these findings derive from small, older cohorts and lack confirmation in more recent studies [6,7].
In dogs, the most common allergen sources involved in food allergy are beef, dairy products, chicken, wheat and lamb. In cats, beef, fish and chicken are the most important [8,9]. The most common allergenic food proteins range between 15 and 40 kDa [3].
In food allergy, intolerance to food antigens may occur due to genetic predisposition, intestinal dysbiosis, alterations in gastrointestinal permeability or in the local immune system [3]. In fact, it is currently accepted that gut and skin microbiome can influence susceptibility to food allergy in children by various mechanisms of immune system modulation [10]. Some authors suggest that the type of acquired hypersensitivity could be explained by the allergenicity of food components at the gastrointestinal tract level [11].
Diagnosing food allergies in dogs and cats can be challenging but, as a general rule, once a food allergy diagnosis is confirmed and the causative ingredients are identified, the prognosis is excellent [12]. The literature reviewed in this article was identified through searches in the PubMed and Scopus databases, as well as by screening reference lists of relevant articles, including publications until 2025. This review aims to summarize the most reliable diagnostic techniques and long-term management options, currently available for dogs and cats with food allergies.

2. Clinical Signs

An animal with food allergy may present with dermatological and/or gastrointestinal manifestations [1].
Non-seasonal pruritus is the most common manifestation of food allergy in dogs and cats, which may be generalized, especially in dogs, or localized [1,5,12]. Face, ears, ventrum and feet are areas commonly affected in both species [1,5,12]. Perianal pruritus and otitis externa may also be observed [1,5,12].
In cats, food allergy can manifest as one of four known skin reaction patterns (miliary dermatitis, head and neck pruritus, symmetrical self-induced alopecia, and feline eosinophilic complex) [5,13] but, according to Bryan and Frank (2010), head and neck are the most affected areas in this species [13]. Plasma cell or erythematous pododermatitis can also be a clinical sign of food allergy in cats [13].
Patients with food allergies are predisposed to secondary fungal and bacterial infections, which can increase the level of pruritus [1,5,12]. Secondary lesions such as lichenification, hyperpigmentation, excoriations and alopecia may also occur [1,12].
Nearly 40% of food allergic dogs present with cutaneous signs before one year of age, while in cats the onset of clinical signs appears to occur later [5]. Furthermore, in dogs, skin lesions may show quite similar to those of environmental-related atopic dermatitis, but clinical signs associated with food allergy generally occur earlier in life than in environmental allergy [12,14].
In more than 20% of dogs and cats with food allergy, the most common non-cutaneous signs are vomiting and diarrhea, but other gastrointestinal signs, like abdominal discomfort, flatulence, borborygmi and frequent defecations can be seen concurrently with the dermatological signs [1,15]. In dogs, some cases of anaphylaxis, conjunctivitis, increased frequency of bowel movements, symmetrical lupoid onychomycosis and sneezing have been described [15]. In cats, conjunctivitis, salivating, flatulence, hyperactive behavior and respiratory signs were reported less commonly [15].
Clinical signs associated with food allergy in dogs and cats are summarized in Table 1.

3. Diagnosis

3.1. Elimination-Provocation Test

The elimination–provocation test remains the gold standard for the diagnosis of food allergy in dogs and cats presenting with non-seasonal pruritus [1,13,16].
Before performing the test, it is recommended to eliminate ectoparasites, such as sarcoptic mites and fleas, and control any secondary infections [12,13].
The elimination diet should last for at least eight weeks in dogs and cats, to achieve a diagnostic sensitivity greater than 90% [1,17]. If there is a clinical improvement during the elimination diet, a challenge test with the original diet should last up to 10 to 14 days [1,13]. A diagnosis of food allergy could be achieved if the previous diet leads to clinical deterioration and if the animal improves again by returning to the elimination diet [1,18].
The elimination diet should be performed by using a homecooked diet, based on a novel protein source. Although, usually, this is not possible because it is laborious and expensive, mainly for large breeds [3,18]. Commercial diets with hydrolyzed proteins or, eventually, a novel protein commercial diet stand as good alternatives. This decision should be based on diet history and dietary preferences of the animal, and the financial possibilities of the owner [18].
Commercial diets require less preparation time but present a higher risk of contamination with other protein sources during manufacturing. Homemade diets are safer in terms of contamination risk, but may be nutritionally unbalanced, especially in young, rapidly growing, large breed dogs [1,12]. Theoretically, homecooked diets also have the advantage of preventing adverse reactions to any food additives, but more studies are needed to prove this hypothesis in relation to commercial pet food [3].
Insect-based diets have been suggested as a novel protein source [3,19]. Nevertheless, these proteins are very similar to those of house dust mites and, for this reason, are not a good alternative for dogs sensitized to allergens from these mites [3]. This phenomenon, called cross-reactivity, occurs when antibodies are produced against a primary sensitizing allergen, but also react with other proteins of similar sequence. This is a major concern even with homecooked diets, because nowadays pet owners typically feed their animals a variety of pet foods, treats, and human food, making it more difficult to select a protein source that the animal has never eaten before [20]. Still, we know that taxonomically closer protein sources may present a greater risk of cross-reactivity [12].
In fact, cross-reactivity between food allergens is an important consideration when planning elimination diets. Serological studies in dogs have shown significant associations between related food pairs such as beef, lamb, and cow’s milk. Inhibition ELISA testing has confirmed cross-reactive IgE-binding epitopes among these sources [21]. These findings suggest that proteins from closely related sources may trigger immune reactions in sensitized animals. However, theoretical allergen similarity models (e.g., A-RISC indices) indicate that cross-reactivity may also occur between more distantly related proteins. Although, clinical confirmation in dogs and cats has been limited [22]. Therefore, careful evaluation of protein homology and, when practical, individual challenge testing can help clarify specific sensitivities and guide elimination diet planning.
In cases of IgE-mediated food allergy, an extensively hydrolyzed diet is a good option for an elimination diet, since the low molecular weight of those hydrolyzed proteins prevents allergen IgE cross-linking and thus mast cell activation [3,23]. In fact, many hydrolyzed diets, such as a hydrolyzed salmon diet or a hydrolyzed poultry feather diet, have been used and have proven useful for diagnosing food allergies [1,24]. Moreover, diets with hydrolyzed protein showed absence or less contamination than novel protein diets [23,25] besides the lower allergenicity of hydrolyzed proteins [1]. Nevertheless, feeding with hydrolyzed diets could not be sufficient to prevent clinical signs associated with food allergy, and one possible explanation is related to the fact that these diets may contain proteins that stimulate helper T-lymphocytes [26].
During the elimination diet period, owners should be advised not to feed their pet any oral flavored medicines or antiparasitic products, food supplements, treats, chew toys, snacks or human food [1,12,13,18,20]. It is important to monitor coprophagic dogs to prevent the ingestion of undigested material [12] and, due to their hunting behavior, cats should be kept indoors [12,20]. In multi-pet households, all animals should be fed the same diet or kept in separate rooms [20]. Cats tend to be more of a challenge to get into the diet and, because of the risk of developing hepatic lipidosis, it is recommended to have an alternative exclusion diet at hand if the cat stops eating [1]. Since cats are obligate carnivores, a homecooked diet only with a meat source is a good option and increases the likelihood of acceptance by the cats [1].
In fact, the most important factor and one of the biggest challenges in ensuring a good elimination protocol is related to owners’ compliance [12,20]. Communication with the owner during the elimination diet is crucial to ensure compliance and identify difficulties with the protocol [1,20].
If no improvement in clinical signs is observed, but there is strong suspicion of food allergy, a second elimination diet with a different protein source should be considered [1,12]. When facing food allergy and a concomitant environmental allergy, interpreting the elimination tests becomes more difficult as clinical signs may not disappear completely [3].
In the initial phase of an elimination diet, anti-inflammatory drugs may be needed to control the signs [12]. Concomitant administration of an anti-inflammatory dose of prednisolone during the first two weeks of the elimination diet can reduce itching and inflammation to a normal level. This protocol, besides useful in reducing the duration of the diet to four to six weeks, may also improve the owner’s compliance to the elimination diet, and reduce the likelihood of secondary infections during this period [27]. Furthermore, oral administrations of glucocorticoids may also have the benefit of increasing animal compliance due to the side effect of polyphagia [20]. Alternatively, oclacitinib may also be used in the initial phase of the elimination diet, to reduce the duration of the protocol [28].
To confirm a diagnosis of food allergy, a challenge test is absolutely necessary to rule out seasonal environmental allergy, since an improvement observed during an elimination diet may be due to seasonal causes [3,12,18]. On the other and, if treatment for ectoparasites or control of a possible secondary infection is carried out simultaneously with the start of the elimination diet, this challenge test can help differentiate the causes of pruritus [12].
The challenge test consists of refeeding the animal its previous diet, including all snacks, treats, and any dietary supplements [3]. However, offering different types of food can result in a more specific diagnosis if each food is introduced one at a time. Typically, clinical signs resulting from an IgE-mediated reaction appear within a few hours after provocation, while a cell-mediated reaction may show signs one to two weeks after the initial challenge [3,20,29]. Currently, cell-mediated reactions are believed to be the most frequent, as most dogs with food allergies show late clinical signs after the challenge test [29,30,31]. Shimakura and Kawano (2021) concluded that in dogs, limbs and face are the main areas affected after a challenge test [30].
Tinsley et al. (2024) revealed that, for a challenge test, one teaspoon of the offending ingredient is enough for the reappearance of food allergy signs [32]. However, more studies are needed to know how much food is needed to cause a flare [20]. When clinical signs reappear, the new diet should be discontinued, returning to the elimination diet, to avoid worsening of clinical signs [20]. Once stable, it is important to introduce a new ingredient every 10–14 days, based on the patient’s dietary history [12,13,20].

3.2. Other Diagnostic Tests

Several alternative in vivo and in vitro tests have been investigated in dogs and cats with suspected food allergy. However, none of these tests have been validated as standalone diagnostic tools, and their clinical utility varies between aiding diagnosis and supporting diet selection.

3.2.1. Adjunctive Tests

These tests should be regarded as adjunctive tools and cannot replace an elimination–provocation test for the diagnosis of food allergy.
Despite their availability, intradermal testing with food antigens and IgE- or IgG-based assays lack sufficient sensitivity and specificity and are therefore not recommended for the diagnosis of food allergy in dogs and cats [1]. Martins et al. (2019) suggested combining in vivo (intradermal tests) and in vitro (immunodot blot) tests for a more reliable and faster diagnosis than a 2-month diet trial [33].
Food-specific IgE determinations in feces, hair and saliva are not recommended for the diagnosis of food allergy. Serum IgE testing for food allergens, while a frequently used diagnostic tool, is also unreliable in dogs and cats [1,3,34,35]. Moreover, overdiagnosis of food allergy, using these tests, may lead owners to feed their animals a diet containing more exotic protein sources, which may be useful for performing an elimination diet if the clinical case truly indicates such diet [35].
It has been suggested that the low utility of IgE tests to identify food allergens that cause reactions in dogs could be explained by the increased IgE levels against components related to beef, resulting from canine vaccination with products containing fetal bovine serum [11]. On the other hand, the cutoff value can vary, depending on the laboratory, and this factor may explain the difference in the number of food allergens identified by each IgE test. Furthermore, there are individual differences, leading to different clinical triggering cutoff values between patients [11].
Similarly, serum Immunoglobulin G (IgG) determination by Enzyme-Linked Immunosorbent Assay (ELISA) is not reliable for the diagnosis of food allergy or for the identification of the allergens responsible for the clinical signs of food allergy in dogs [36].
In turn, the patch tests are not useful for diagnosing food allergy in dogs but can be a good tool for selecting a protein source for an elimination diet [37]. Combining these tests with skin prick tests appears to be an even more effective protocol for this selection [38]. Western blot may also be useful for selecting an elimination diet, but not for diagnosing food allergies [39,40].
While most adjunctive tests show limited diagnostic value, some approaches aim to better reflect the underlying immunopathogenesis of food allergy and are currently under investigation.
Compared to healthy dogs, the lymphocyte provocation test proved to be more accurate in detecting the association between test results and clinical signs than the common IgE-based tests (serological, intradermal or prick tests), probably because most food allergies in dogs could be explained by a lymphocyte-mediated reaction, and not by an IgE-mediated reaction [11,31]. Suto et al. (2015) [41] suggested that atopic-like dermatitis might actually be caused by a type IV hypersensitivity-mediated food-allergy. By studying 54 dogs with history and clinical signs compatible with atopic dermatitis, but with negative IgE test results, they verified that 90.7% of the studied animals had positive lymphocyte reactions against one or more food allergens [41]. The delayed food allergy response (suspected of a cell-mediated mechanism) to oral food challenges (OFC) seemed to be the most common type of food allergy in dogs as it has been highlighted by Olivry and Mueller (2020), who pointed that only 9% of dogs submitted to OFC with the implicated food, showed a return of symptoms during the first day upon challenge [29]. Recently, Fernandez-Lozano et al. (2025) [31] developed a lymphocyte proliferation test (LPT), using co-cultures of canine peripheral blood mononuclear cells (PBMCs) with food allergens and were able to detect dogs with delayed food allergies. The study was conducted only on dogs with delayed reactions after the food challenge test, as those were suspected of having cell-mediated food allergies, and, in this way, it was possible to achieve 100% sensitivity and 100% specificity for this test. The authors also pointed out as an advantage of this technique, the possibility of direct determination of cell count, without the need for radioactive isotopes or an expensive flow cytometer. In a practical way, this test makes it possible to identify the food components that cause flares in dogs with delayed food allergies [31]. Despite the need for further multicenter validation with larger sampling, LPT studies may help differentiate delayed from immediate food allergy, a suspected IgE-mediated condition.

3.2.2. Emerging Tools

Emerging diagnostic tools are currently being developed to improve the identification of immunological sensitization patterns; however, their role in the diagnosis of food allergy remains limited and they should not be used as standalone tests.
In 2024, Olivry and his team developed and validated a quantitative macroarray for the determination of IgE sensitizations in dogs and cats—Pet Allergy Xplorer (PAX®) from Nextmune (Stockholm, Sweden), including molecular environmental and food allergens, which allows differentiation between cross-reactivity and primary sensitization [42]. However, only occasionally the PAX-test detects serum specific IgE associated with the offending food allergens [31].
Despite promising preliminary results, most alternative and emerging diagnostic tests for food allergy in dogs and cats are supported by studies with small sample sizes, limited external validation, and heterogeneous methodologies. In many cases, investigations are conducted in single-center settings or under experimental conditions, which may limit their reproducibility and clinical applicability. Additionally, some commercially available assays lack independent multicenter validation, increasing the risk of overinterpretation or false-positive results. Therefore, while these tools may provide complementary information or assist in diet selection, they should be interpreted cautiously and cannot replace the elimination–provocation test as the diagnostic gold standard. Taking these limitations into account, Figure 1 summarizes a pragmatic diagnostic approach that prioritizes validated methods while integrating adjunctive and emerging tools when clinically appropriate.

4. Therapeutic Approaches

The main goal of food allergy treatment is to avoid the allergens responsible for the clinical signs [18,20]. This is the foundation of therapy and cannot be replaced by pharmacological interventions alone.

4.1. Dietary Management

For long-term management of a food-allergic animal, this can be fed with a novel protein diet, a hydrolyzed diet or another commercial diet lacking offending-allergens [3,18,20]. A homecooked diet can be an option, but it is recommended to be formulated by a veterinary nutritionist, especially regarding cats [13,18,20]. For cats, palatability is also important when choosing a lifelong diet [13].
Cross-reactivity between protein sources should be considered when designing the diet, to avoid unexpected allergic reactions.
The main concern regarding the use of commercial novel protein diets is the possibility of contamination of these diets with other protein sources [43]. Pagani et al. (2018) analyzed 11 antigen-limited wet diets, by Polymerase Chain Reaction (PCR), and demonstrated the presence of animal proteins not mentioned on the label, with a cross-contamination of 54.5% [44]. Ricci et al. (2018) studied 38 pet diets, used during the elimination diet protocol, and found that 75% were contaminated with other animal species not listed on the label [25]. However, recent data indicate that strict industrial manufacturing practices, including dedicated production lines, rigorous cleaning procedures, and routine DNA- and protein-based analytical verification, can markedly reduce the risk of cross-contamination. In extensively hydrolyzed diets produced under such quality control systems, more than 99.9% of tested batches complied with predefined contamination thresholds [23]. These findings suggest that, although contamination remains a concern for some commercial diets, advances in quality assurance can enhance the reliability of carefully selected products for diagnostic and management purposes.

4.2. Pharmacological Therapy

In case of accidental ingestion of an offending-allergen, short-term pharmacological interventions can be used for faster control of the clinical signs and provide rapid relief [3,20]. These include antipruritic agents such as oral or topical glucocorticoids, lokivetmab or Janus-kinase inhibitors, depending on the severity of pruritus and the patient’s overall condition [18,20].
The choice of drug, dose, and duration should be tailored to the individual patient, considering factors such as age, comorbidities, and previous response to therapy. Short-term use is recommended to minimize potential adverse effects, especially when repeated exposures occur [18].

4.3. Adjunctive Therapies

Adjunctive therapies include experimental or emerging options such as sublingual immunotherapy (SLIT) with food antigens and modulation of the gut–skin axis.
Sublingual immunotherapy with food antigens has been explored as a potential treatment for dogs with confirmed food allergy. Available studies suggest that SLIT is generally safe and well tolerated, with minimal adverse effects reported [45,46]. In a small, comparative, double-blind, randomized, placebo-controlled study, SLIT for canine food allergy significantly reduced itching and skin lesions, demonstrating preliminary efficacy [45].
However, the study population was limited, and additional research is needed to confirm long-term efficacy and safety, particularly across different breeds, age groups, and comorbidities. Given the small size and preliminary nature of available trials, SLIT should currently be considered an experimental approach, and if used, it should be initiated under veterinary supervision with careful monitoring during the initial stages.
The gut–skin axis represents a functional connection between the intestinal and cutaneous barriers, mediated by the microbiota, which modulates immune responses and contributes to epithelial barrier integrity. Dysbiosis in either the gut or skin has been associated with increased susceptibility to allergic skin conditions in dogs, like food allergy [47]. This emphasizes the importance of maintaining a balanced gut microbiota for skin health in food-allergic patients.
Interventions such as dietary changes, probiotics, prebiotics, postbiotics, and fecal microbiota transplantation are promising strategies for modulating the microbiota and reducing the use of antimicrobials, helping to decrease antimicrobial resistance [47]. However, the efficacy of probiotics and related interventions can vary depending on strains, formulations, and dosing regimens, and should be interpreted cautiously in clinical practice.
An example of this are the results of the study by Noli et al. (2023) [48], in which forty allergic dogs with dermatological signs were studied before and after feeding a hypoallergenic diet based on hydrolyzed fish/rice starch, for eight weeks. Fecal samples were collected pre- and pos-diet, and the authors concluded that the rice in this diet modified the microbiota, promoting the development of bacteria responsible to produce short-chain fatty acids, essential for intestinal homeostasis. Dogs fed this diet showed a reduction in the prevalence of Bacteroidetes, a characteristic of dysbiotic dogs [48].
Table 2 summarizes the main therapeutic strategies described above and Figure 2 presents a suggested therapeutic management flowchart for acute flares and long-term control.

5. Conclusions

Food allergy remains a diagnostic and therapeutic challenge in dogs and cats, mainly due to the absence of reliable biomarkers and the need for time-consuming elimination-provocation tests. However, recent advances are reshaping the future of diagnosing this condition. The development of molecular allergen macroarrays such as the Pet Allergy Xplorer (PAX®) and the lymphocyte proliferation assays will allow a better understanding of the immunopathogenesis of delayed-type reactions, opening new perspectives for precision diagnostics.
From a therapeutic point of view, immunotherapy using food antigens, modulation of the gut–skin axis through pre-, pro- and postbiotics, and the refinement of hydrolyzed protein diets represent promising strategies to improve long-term management. These approaches can also reduce the need of anti-inflammatory drugs and antibiotics, as well as promote the balance of the gut microbiota.
The future of food allergy management in companion animals will depend on the integration of traditional clinical approaches with molecular, immunological, and microbiome-based tools. Larger controlled studies are needed to validate these emerging diagnostic and therapeutic options, aiming at a more personalized, efficient, and well-being-focused care for allergic dogs and cats.

Author Contributions

Conceptualization, D.M. and L.M.; methodology, D.M.; investigation, D.M.; writing—original draft preparation, D.M.; writing—review and editing, D.M. and L.M.; supervision, L.M.; project administration, L.M.; funding acquisition, L.M. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by National Funds through FCT—Foundation for Science and Technology under the Project UIDB/05183.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

No new data were created or analyzed in this study. Data sharing is not applicable to this article.

Acknowledgments

The authors wish to thank MED (https://doi.org/10.54499/UIDP/05183/2020) & CHANGE (https://doi.org/10.54499/LA/P/0121/2020).

Conflicts of Interest

The authors declare no conflicts of interest.

Abbreviations

The following abbreviations are used in this manuscript:
IgEImmunoglobulin E
ELISAEnzyme-Linked Immunosorbent Assay
IgGImmunoglobulin G
OFCOral Food Challenges
LPTLymphocyte Proliferation Test
PBMCsPeripheral Blood Mononuclear Cells
PAXPet Allergy Xplorer
PCRPolymerase Chain Reaction
SLITSublingual immunotherapy

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Applsci 16 02169 g001
Figure 1. Proposed diagnostic algorithm for food allergy in dogs and cats.
Figure 1. Proposed diagnostic algorithm for food allergy in dogs and cats.
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Figure 2. Suggested therapeutic management of food allergy in dogs and cats.
Figure 2. Suggested therapeutic management of food allergy in dogs and cats.
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Table 1. Clinical signs associated with food allergy in dogs and cats.
Table 1. Clinical signs associated with food allergy in dogs and cats.
Clinical FeatureDogsCats
Most common
cutaneous signs		Non-seasonal pruritus
Erythema
Papules
Pododermatitis
Otitis externa		Non-seasonal pruritus
Skin reaction patterns (miliary dermatitis, head and neck pruritus, symmetrical self-induced alopecia, feline eosinophilic complex)
Skin lesions
distribution		Face, ears, ventral abdomen, paws, perianalFace, neck, ventral abdomen
Most common
gastrointestinal signs		Vomiting
Diarrhea		Vomiting
Diarrhea
Less common signsAbdominal discomfort
Flatulence and borborygmi
Frequent defecations
Anaphylaxis
Conjunctivitis
Symmetrical lupoid onychomycosis
Sneezing		Pododermatitis
Otitis externa
Conjunctivitis
Salivating
Flatulence
Hyperactive behavior
Respiratory signs
Table 2. Main therapeutic strategies for managing food allergy in dogs and cats.
Table 2. Main therapeutic strategies for managing food allergy in dogs and cats.
Therapeutic CategoryExamples
Dietary managementNovel protein diet
Hydrolyzed diet
Home-cooked diet
Short-term pharmacological therapyOral/topical glucocorticoids
Lokivetmab
Janus-kinase inhibitors
Adjunctive therapiesSLIT with food allergens
Gut–skin axis modulation (probiotics, prebiotics, postbiotics, fecal microbiota transplantation)
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Matias, D.; Martins, L. Food Allergy in Companion Animals: Integrating Traditional Diagnostics with Emerging Approaches. Appl. Sci. 2026, 16, 2169. https://doi.org/10.3390/app16052169

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Matias D, Martins L. Food Allergy in Companion Animals: Integrating Traditional Diagnostics with Emerging Approaches. Applied Sciences. 2026; 16(5):2169. https://doi.org/10.3390/app16052169

Chicago/Turabian Style

Matias, Daniela, and Luís Martins. 2026. "Food Allergy in Companion Animals: Integrating Traditional Diagnostics with Emerging Approaches" Applied Sciences 16, no. 5: 2169. https://doi.org/10.3390/app16052169

APA Style

Matias, D., & Martins, L. (2026). Food Allergy in Companion Animals: Integrating Traditional Diagnostics with Emerging Approaches. Applied Sciences, 16(5), 2169. https://doi.org/10.3390/app16052169

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