Skin problems in dogs and cats:
the gut-skin axis and the integrative protocol
Itching, eczema and chronic skin inflammation are rarely purely local. The role of gut microbiome, immune regulation, and systemic inflammation. Substantiated with literature and with links to deepening on all three NGD platforms.
By Stefan Veenstra DVM
Skin as a mirror of systemic imbalance
In integrative veterinary medicine, skin is not seen as an isolated organ but as a mirror of the overall physiological balance. Chronic skin complaints in dogs and cats: itching, eczema, recurrent infections, hair loss, oily or scaly skin. In most cases, these are expressions of an underlying systemic process: immune dysregulation, gut dysbiosis, chronic low-grade inflammation, toxic load or stress-related neuroimmunological activation. [1]
This perspective has direct consequences for the treatment strategy. A purely local approach, such as shampoos, corticosteroids and antihistamines, addresses the symptoms but not the underlying imbalance. A sustainable improvement requires intervention at the system level: the gut microbiome, immune balance, inflammation regulation and skin barrier function all at the same time.
Read on StefanVeenstra.nl: skin as a system expression. The Systems Biology Approach to Chronic Skin Problems
Read on NatuurlijkGezondeDieren.nl: integrative dermatology in dogs and cats: clinical applications and case studies
The gut-skin axis: mechanistically substantiated
The relationship between gut microbiome and skin health has been one of the most researched links in immunology over the past decade. The concept of the “gut-skin axis” describes how dysbiosis in the gut is controlled via increased intestinal permeability, systemic endotoxemia, and immune activation. This contributes to skin inflammation, allergic reactions and disrupted skin barrier function at a distance from the intestine. [2]
In dogs with atopic dermatitis, gut dysbiosis has been consistently demonstrated, with reduced microbiome diversity and a relative reduction in Lactobacillus and Bifidobacterium species, similar to the dysbiosis pattern in human atopy. [3] This makes gut support a mechanistically well-founded part of any chronic skin protocol.
View the NGD Care Bowel Protocol: recommended supplement for chronic skin complaints
The four components of the Skin Protocol
Histamine Balance: antihistamine and anti-inflammatory
Methylsulfonylmethane (MSM) is an organic sulfur compound that provides bioavailable sulfur for collagen synthesis, keratin production, and glutathione biosynthesis. [4] Sulfur is an essential building block of skin structure and plays a direct role in the integrity of the stratum corneum. In addition, MSM has anti-inflammatory and antipruritic properties via inhibition of NF-κB signaling and modulation of prostaglandin production. [5]
Quercetin is a flavonoid with clinically relevant antihistamine activity: it inhibits mast cell degranulation. The direct trigger of histamine release in allergic reactions and downregulates the expression of histamine receptors. [6] When combined with MSM, a dual approach to both the acute histamine response and the underlying inflammatory response emerges. In dogs with atopic dermatitis and food allergy, this mechanism is directly relevant.
PEA Complex: inflammatory modulation without side effects
Palmitoylethanolamide (PEA) modulates the inflammatory response via PPAR-alpha activation and mast cell degranulation inhibition. A mechanism that is relevant both in the intestine and in the skin. [7]
Boswellia serrata selectively inhibits 5-lipoxygenase and thus the leukotriene pathway, a branch of the inflammatory cascade that plays a central role in skin inflammation. [8] The combination provides broader inflammation modulation than either ingredient alone, without the side effects of corticosteroids or NSAIDs that pose a real problem with chronic skin use.
Why not just corticosteroids?
Corticosteroids are effective in acute allergic skin reactions but have known drawbacks when used for a long time: adrenocortical suppression, increased susceptibility to infection, polyuria/polydipsia and skin atrophy. For chronic skin problems. When months or even years of support are required, non-steroidal modulators such as PEA, boswellia and quercetin are mechanistically more relevant and safer for long-term use.
Myco Immune Complex: immune balance via medicinal mushrooms
Medicinal mushrooms contain beta-glucans and other polysaccharides that modulate the innate immune system via toll-like receptor 2 and dectin-1. [9] In allergic skin disease, the central immunological disruption is a dominant Th2 response. The direction that also characterizes asthma and food allergy. Beta-glucans from mushrooms such as Reishi (Ganoderma lucidum), Maitake (Grifola frondosa), and Shiitake (Lentinula edodes) stimulate the Th1 arm of the immune system and help restore Th1/Th2 balance without suppressing immune function. [10]
This makes Myco Immune Complex a strategic part of the skin protocol: it does not address the symptoms but the immunological root cause of the allergic overreaction.
Calanus oil: omega-3 and astaxanthin for the skin barrier
Calanus oil is extracted from the marine copepod Calanus finmarchicus and differs from conventional fish oil by a special fatty acid profile: in addition to EPA and DHA, it contains stearidон acid (SDA), an omega-3 fatty acid that is converted to EPA more efficiently than vegetable omega-3 sources. [11] The fatty acids are bound as wax esters instead of triglycerides, which improves bioavailability and absorption.
Omega-3 fatty acids are essential for skin barrier function via their role in the phospholipid composition of cell membranes and the stratum corneum. EPA additionally modulates the arachidonic acid pathway and shifts the ratio between pro-inflammatory (AA-derived) and anti-inflammatory (EPA-derived) eicosanoids in favor of the latter. [12] Also, it contains astaxanthin, a carotenoid antioxidant in calanus oil, protects skin cells from UV-induced and inflammatory oxidative damage with an antioxidant power that far exceeds that of vitamin E. [13]
Additional protocol elements
For stress-related itching: Adaptogen complex, Myco Adaptogen Complex and CBD oil
Stress activates the HPA axis and increases cortisol production, which directly affects the skin via increased mast cell activity and lowered barrier function. [14] In animals where stress-related itching is a clear component (seasonal, environmental or behavioral), our Adaptogen complex with Ashwagandha and rhodiola or the Myco Adaptogen Complex (mushroom mix 2) can be added. Adaptagenic mushrooms such as Ashwagandha and Rhodiola modulate the stress response via the HPA axis and lower the cortisol response in chronic stress. CBD oil provides additional support through the endocannabinoid system, which plays a direct role in the regulation of mast cells, keratinocytes and sebaceous glands in the skin.
For chronic complaints: Bowel protocol as a basis
For every dog or cat with recurring or chronic skin problems, it is urgently recommended to combine the Skin Protocol with the NGD Care Intestinal Protocol. The gut-skin axis is almost always a relevant mechanistic focus in chronic atopy. Without restoration of gut barrier and microbiome balance, the skin protocol continues to work symptomatically instead of addressing the underlying imbalance.
NGD Care Bowel Protocol. The basis for chronic skin and immune problems
Local support: ozone cream and colloidal silver-zinc spray
For acute eczema patches, wet eczema or infected skin areas, local support can be added. Ozone has demonstrated antimicrobial and wound healing properties via oxidative disinfection without resistance build-up. [15] Colloidal silver combined with zinc has antimicrobial activity and supports skin repair via zinc-dependent enzymes in wound healing.
The NGD Care Bowel Protocol: summary for chronic skin complaints
For every dog or cat with recurring or chronic skin problems, the Intestinal Protocol is the mechanistic logical basis. The gut-skin axis is almost always a relevant point of attention in chronic atopy. Without restoration of intestinal barrier and microbiome balance, the skin protocol continues to work symptomatically.
Food intervention phase: continuous basis
Approximately 80% fresh or wet food, approximately 20% vegetables. Ultra-processed dry food increases the glycemic load of the gut, promotes unwanted microbiome shifts and maintains low-grade inflammation. Nutrition is not an afterthought but a prerequisite for effective intestinal recovery.
Phase 1: Cleansing and breaking down biofilm (weeks 1–8)
Enzyme mix 2 breaks down pathogenic biofilm in the intestine. Liposomal Curcumin and Vitamin C inhibit low-grade inflammation. Chlorella-Spirulina-Alfalfa supports detoxification. Prebiotics stimulate a favorable intestinal flora as a basis for the build-up phase. This is a targeted reset of the intestinal environment. Not symptom control.
Phase 2: Build up and recover (weeks 8–16)
Intestinal wall restoration via water kefir, L-glutamine (direct fuel for enterocytes and tight junction repair) and shilajit or fulvic and humic acids. Support enzymatic digestion and supplement deficiencies via Liposomal Vitamin B Complex. For humans, shilajit is the preferred choice at this stage. Only when the intestine is clean and calm, build-up is effective and permanent.
Scope of application of the Skin Protocol
Atopic dermatitis and allergic skin reactions. Chronic itching, eczema and recurrent skin inflammations. Food allergy with skin manifestation. Stress-related skin complaints. Skin problems with immune dysregulation or after long-term corticosteroid use. Supporting the skin barrier for dry, flaky or fragile skin. Always in consultation with an (integrative) veterinarian, especially in case of long-term or serious complaints.
Conclusion
Skin problems in dogs and cats require a system-oriented approach. The NGD Care Skin Protocol addresses the four main mechanisms: allergic immune activation, underlying inflammation, skin barrier dysfunction and immune imbalance, through four complementary supplements, each with its own mechanism of action.
In the case of chronic complaints, supplementation with the Bowel Protocol is mechanistically necessary. For stress-related itching, Myco Adaptogen Complex and CBD are relevant supplements. Local support with ozone or silver-zinc spray completes the protocol for acute spots.
For the deeper systemic biology background of chronic skin problems, we refer to the pages on StefanVeenstra.nl and NatuurlijkGezondeDieren.nl. The links are in the text above.
View the NGD Care Skin Protocol in the webshop
Literature
- Marsella R, Sousa CA, Gonzales AJ, Fadok VA. Current understanding of the pathophysiologic mechanisms of canine atopic dermatitis. J Am Vet Med Assoc. 2012; 241(2):194–207.
- Salem I, Ramser A, Isham N, Ghannoum MA. The gut microbiome as a major regulator of the gut-skin axis. Front Microbiol. 2018;9:1459.
- Rodrigues Hoffmann A, Patterson AP, Diesel A, et al. The skin microbiome in healthy and allergic dogs. PLoS One. 2014; 9(1):E83197.
- Parcell S. Sulfur in human nutrition and applications in medicine. Altern Med Rev. 2002; 7(1):22–44.
- Amirshahrokhi K, Bohlooli S, Chinifroush MM. The effect of methylsulfonylmethane on the experimental colitis in the rat. Toxicol Appl Pharmacol. 2011; 253(3):197–202.
- Finn DF, Walsh JJ. Twenty-first century mast cell stabilizers. Br J Pharmacol. 2013; 170(1):23–37.
- Petrosino S, Di Marzo V. The pharmacology of palmitoylethanolamide and first data on the therapeutic efficacy of some of its new formulations. Br J Pharmacol. 2017; 174(11):1349–1365.
- Siddiqui MZ. Boswellia serrata, a potential antiinflammatory agent: an overview. Indian J Pharm Sci. 2011; 73(3):255–261.
- Akramiene D, Kondrotas A, Didziapetriene J, Kevelaitis E. Effects of beta-glucans on the immune system. Medicina (Kaunas). 2007; 43(8):597–606.
- Guggenheim AG, Wright KM, Zwickey HL. Immune modulation from five major mushrooms: application to integrative oncology. Integr med (encinitas). 2014; 13(1):32–44.
- Nanton V, Rustan AC, Lund E, et al. Dietary administration of Calanus finmarchicus oil influences the tissue fatty acid composition of Atlantic salmon. Aquacult Nutr. 2015; 21(3):309–319.
- Calder PC. Omega-3 fatty acids and inflammatory processes: from molecules to man. Biochem Soc Trans. 2017; 45(5):1105–1115.
- Ambati RR, Phang SM, Ravi S, Aswathanarayana RG. Astaxanthin: sources, extraction, stability, biological activities and its commercial applications: a review. But drugs. 2014; 12(1):128–152.
- Slominski A, Wortsman J. Neuroendocrinology of the skin. Endocr Rev. 2000; 21(5):457–487.
- Elvis AM, Ekta JS. Ozone therapy: a clinical review. J Nat Sci Biol Med. 2011; 2(1):66–70.
This information is educational in nature and based on available scientific literature. The studies mentioned are not always directly veterinary or specific to the formulation described here. This text does not replace a veterinary consultation and does not contain any therapeutic claims.