Addison's Disease & Diet: Feeding a Dog with Hypoadrenocorticism

If your dog has been diagnosed with Addison’s disease — the medical term is hypoadrenocorticism, also known as adrenal insufficiency — you may have noticed the condition is something of a diagnostic journey. Addison’s is notoriously easy to miss because its symptoms (lethargy, vomiting, poor appetite, shaking) overlap with dozens of other conditions. Once diagnosed, the good news is that most dogs respond extremely well to treatment and go on to live full, normal lives.

Diet is not the primary treatment for Addison’s disease — that role belongs to hormone replacement therapy. But feeding the right foods, understanding which nutrients need careful management, and knowing what to do during acute episodes can meaningfully support your dog’s wellbeing and reduce the risk of complications. This article explains the dietary logic behind Addison’s disease management and gives practical guidance for both the crisis period and long-term maintenance.

What Addison’s Disease Does to the Body

The adrenal glands sit just in front of the kidneys and produce two critical hormone groups: glucocorticoids (primarily cortisol) and mineralocorticoids (primarily aldosterone). In Addison’s disease, the adrenal cortex fails — usually due to immune-mediated destruction — and production of both hormone types falls dangerously low.

Each hormone has distinct effects:

• Aldosterone regulates electrolyte balance. It tells the kidneys to retain sodium and excrete potassium. Without aldosterone, sodium pours out in the urine while potassium accumulates in the blood.
• Cortisol regulates blood sugar, inflammation, and the body’s stress response. Without cortisol, dogs cannot mount an effective response to physical stress — illness, injury, or even a long car journey can trigger a life-threatening collapse.

The electrolyte disruption — low sodium (hyponatraemia), high potassium (hyperkalaemia) — is the key dietary consideration. Elevated blood potassium can cause cardiac arrhythmias; depleted sodium causes weakness, dehydration, and circulatory collapse. These are the imbalances that dietary management must support (Baumstark et al., JVIM 2014).

Addison’s disease sits at the opposite end of the adrenal spectrum from Cushing’s disease, which involves chronic excess of cortisol rather than deficiency.

Sodium and Potassium: The Core Dietary Concern

Why Sodium Matters in Addison’s Disease

Because aldosterone deficiency causes the kidneys to excrete sodium, dogs with Addison’s disease are at baseline risk of low blood sodium. During stable, well-medicated periods — when mineralocorticoid replacement (typically desoxycorticosterone pivalate / DOCP or fludrocortisone — AAHA 2023 Guidelines) is keeping electrolytes in balance — sodium intake from diet does not usually need to be dramatically elevated. Most standard commercial dog foods provide adequate sodium for a medicated Addisonian dog.

However, there are scenarios where sodium support matters:

• During and after an Addisonian crisis — acute adrenal failure causes rapid sodium loss. Intravenous saline is used in the hospital, and once home, a slightly higher sodium diet can help support recovery while hormone levels are being stabilised.
• During hot weather or heavy exercise — both cause sodium loss through panting and physical exertion. Addisonian dogs may be more susceptible to salt depletion under these conditions.
• If medication dosing is being adjusted — electrolytes may fluctuate during dose titration. Your vet should guide dietary changes during this period.

Potassium: What to Limit

High blood potassium (hyperkalaemia) is the other side of the electrolyte problem. Before diagnosis or during a crisis, potassium climbs to potentially dangerous levels — sometimes causing bradycardia (slow heart rate) or cardiac arrhythmias.

Once medicated, most Addisonian dogs maintain normal potassium levels. But it remains sensible to avoid feeding foods that are unusually high in potassium, particularly if:

• The dog is newly diagnosed and medication is being titrated
• Recent bloodwork shows potassium trending toward the high end of normal
• The dog has a concurrent condition affecting potassium metabolism

High-potassium foods to moderate or avoid:

• Bananas (a common treat that should be used very sparingly)
• White potatoes and sweet potatoes, especially boiled or steamed
• Cooked lentils and legumes
• Tomato paste and concentrated tomato products
• Spinach in large quantities

This does not mean these foods can never be given — a small amount of sweet potato in a commercial food is unlikely to cause problems in a well-medicated dog. The concern is with large quantities or concentrated forms, particularly during the adjustment phase.

The electrolyte imbalances of Addison’s disease also share some similarities with those seen in dogs with kidney disease — both conditions affect the kidneys’ ability to regulate sodium and potassium, though by different mechanisms.

Stress-Feeding During and After an Addisonian Crisis

An Addisonian crisis is a medical emergency — acute adrenal failure causing cardiovascular collapse, severe weakness, vomiting, and hypothermia. It requires immediate veterinary intervention with intravenous fluids, glucocorticoids, and mineralocorticoids.

Once the acute phase is stabilised and the dog is sent home (or during the final stages of hospital recovery), dietary management plays a supportive role.

Principles of Post-Crisis Feeding

Start small and bland. During the recovery window — typically 48–72 hours after a crisis — the gastrointestinal tract is often unsettled. Begin with small, easily digestible meals:

• Boiled white rice with lean boiled chicken (no skin, no seasoning)
• Small amounts of scrambled egg
• A low-fat commercial recovery diet if recommended by your vet

Feed frequently. Three to four small meals per day reduces the digestive burden and helps maintain blood glucose, which cortisol deficiency can cause to drop (glucocorticoid supplementation addresses this medically, but small regular meals provide additional stability).

Avoid high-fat or rich foods during the recovery period. Stressed GI systems handle fat poorly, and an Addisonian dog recovering from a crisis does not need the added challenge of fat digestion.

Transition back to normal food gradually. Once the dog is eating well and holding food down — usually within 3–7 days — slowly reintroduce their regular diet over 4–5 days.

Preventing Future Crises Through Feeding

One underappreciated aspect of long-term Addison’s management is the role of meal consistency. Irregular feeding, skipped meals, or large infrequent meals can cause blood glucose instability that places additional stress on a cortisol-deficient system. Regular, predictable feeding times are a simple but effective part of crisis prevention.

Supporting the Glucocorticoid-Deficient Dog

Without adequate cortisol, dogs have a blunted inflammatory response and reduced capacity for muscle protein synthesis. The right nutritional profile helps support these functions:

Adequate, High-Quality Protein

Cortisol plays a role in muscle protein maintenance. Its deficiency can contribute to muscle weakness and poor muscle condition, particularly in dogs whose Addison’s disease was diagnosed after a prolonged period of symptoms. A diet with adequate high-quality protein — from named whole protein sources such as chicken, fish, lamb, or eggs — supports lean muscle maintenance.

Avoid unnecessarily protein-restricted diets unless a concurrent condition (such as kidney disease) requires it and your vet has specifically recommended this.

Anti-Inflammatory Omega-3 Fatty Acids

The cortisol deficiency in Addison’s disease means the body’s natural anti-inflammatory capacity is reduced (and is partially replaced by glucocorticoid medication). Dietary omega-3 fatty acids from marine sources — eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from fish oil — provide additional anti-inflammatory support at the cellular level (Trastoy-Pena et al., Front Vet Sci 2021).

A measured dose of fish oil appropriate to your dog’s weight, confirmed with your vet, can complement the glucocorticoid replacement therapy without significant risk.

Digestibility as a Priority

Addisonian dogs often have a history of gastrointestinal symptoms — vomiting, diarrhoea, reduced appetite — particularly before diagnosis and around the time of crises. Prioritising highly digestible foods reduces GI workload and ensures nutrients are actually absorbed rather than passed through.

Look for:

• Commercial foods with named protein sources as the primary ingredient
• Moderate fat content (not extremely low, but not high)
• Minimal artificial additives, colours, and flavours
• Foods designed for sensitive stomachs or labelled as “highly digestible”

Long-Term Maintenance Diet

Once an Addisonian dog is stable on appropriate hormone replacement therapy and the vet confirms electrolytes are well controlled on routine blood tests, the dietary approach is less restrictive than in the crisis or titration phases.

What a Good Maintenance Diet Looks Like

• Moderate sodium — not deliberately high, but also not restricted. Standard commercial dog foods are generally appropriate. Avoid specifically sodium-restricted diets unless there is a concurrent cardiac or kidney condition requiring this.
• Moderate potassium — avoid foods unusually rich in potassium, but no need to eliminate potassium-containing foods entirely.
• High-quality protein for muscle maintenance.
• Consistent, regular feeding schedule — predictability supports blood glucose and reduces physiological stress.
• Adequate hydration — encourage water intake, particularly in warm weather or after exercise.

Body Weight and Energy Management

Addison’s disease does not typically cause weight gain the way Cushing’s disease does — in fact, many dogs lose weight during the diagnostic period due to poor appetite. Once stabilised, body weight usually normalises. If your dog is recovering from significant weight loss, a slightly energy-dense food during the repletion period can help rebuild body condition, but avoid pushing the dog to be overweight — obesity worsens many secondary health risks, and an Addisonian dog does not need additional metabolic burden.

Exercise and Activity

Addisonian dogs on adequate hormone replacement can usually exercise normally. However, sudden intense exertion can deplete electrolytes more rapidly in some dogs. Your vet may recommend a stress-dose glucocorticoid protocol for particularly demanding activities (long hikes, dog sports, travel). Always ensure fresh water is available during and after exercise.

What to Avoid

Monitoring and Vet Involvement

Diet adjustment in Addison’s disease is closely tied to the medical management. Electrolyte monitoring — blood sodium and potassium — happens regularly during the early treatment phase and then at routine check-ups once stable. These results should guide any dietary adjustments.

If your dog’s bloodwork shows potassium trending high despite medication, reducing high-potassium food sources is a reasonable step to discuss with your vet. If sodium is consistently low, your vet may recommend a slightly higher-sodium diet alongside reviewing the medication dose.

Never change an Addisonian dog’s diet dramatically without checking with your vet — particularly around sodium, which interacts directly with the hormone replacement regimen.

Frequently Asked Questions

Can an Addisonian dog eat a raw diet? Addisonian dogs on glucocorticoid replacement therapy have relative immunosuppression. The WSAVA Global Nutrition Committee advises against raw meat-based diets for immunocompromised animals due to elevated bacterial contamination risk (Salmonella, Listeria, E. coli). Raw feeding is not recommended for this population without explicit veterinary clearance.

Should I give my Addisonian dog extra salt? Not routinely. A well-medicated dog on appropriate mineralocorticoid replacement should maintain adequate sodium through a normal diet. Some owners of dogs that struggle with low sodium despite medication may use a small amount of added salt or a sodium-containing broth under veterinary guidance — but this should always be directed by bloodwork results, not done speculatively.

Can Addison’s disease cause low blood sugar? Yes — glucocorticoid deficiency reduces the body’s ability to maintain blood glucose, particularly during periods of stress, fasting, or illness (Cornell Canine Health Center). This is managed primarily through glucocorticoid replacement, but regular small meals help provide dietary glucose support. If your dog shows signs of hypoglycaemia (weakness, disorientation, trembling), contact your vet immediately.

Are there commercial diets specifically for Addisonian dogs? No commercial diet is specifically formulated for Addison’s disease. The condition is managed medically, and most standard high-quality commercial foods are appropriate for stable Addisonian dogs. The focus should be on a highly digestible, nutritionally complete food without extreme potassium content or sodium restriction.

What happens to diet if an Addisonian dog develops another condition? This requires careful individual assessment. Concurrent kidney disease, heart disease, or diabetes all have their own dietary requirements that may conflict with Addison’s management (for example, kidney diets restrict protein and sodium, which could be counterproductive). Work with your vet — and possibly a veterinary nutritionist — to navigate multi-condition diets.

Addison’s disease requires lifelong medication, but it is a manageable condition. Diet plays a supporting role: stabilising electrolytes, providing digestible high-quality nutrition, and reducing physiological stress through consistent, appropriate feeding. If you would like help building a tailored nutrition plan for your Addisonian dog — particularly if there are concurrent conditions to manage — contact us for a consultation.

Always manage Addison’s disease under veterinary supervision. This article provides educational information about dietary support and does not replace veterinary diagnosis, examination, or treatment.

Sources

1. Baumstark ME et al. Evaluation of aldosterone concentrations in dogs with hypoadrenocorticism. J Vet Intern Med. 2014.
2. AAHA Selected Endocrinopathies of Dogs and Cats Guidelines 2023 — Canine Hypoadrenocorticism. American Animal Hospital Association.
3. Trastoy-Pena R et al. Therapeutic Effect of EPA/DHA supplementation in companion animal diseases: a systematic review. Front Vet Sci. 2021.
4. WSAVA Global Nutrition Committee. Statement on the risks of raw meat-based diets. 2020.
5. Cornell University College of Veterinary Medicine. Addison’s Disease.