# Addison's Disease in Cats: Treatment Options Addison's disease in cats treatment centers on replacing the hormones the adrenal glands can no longer make. Most cats need daily medication for life, plus regular blood tests to keep doses on track. It is a rare disease, but with the right plan most cats go on to live normal lives. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Quick Answer - Addison's disease (hypoadrenocorticism) means the adrenal glands do not make enough cortisol, aldosterone, or both [1]. - Treatment is lifelong and highly successful in most cases, using a glucocorticoid such as prednisolone and often a mineralocorticoid such as desoxycorticosterone pivalate (DOCP) [1][2]. - Cats often need higher doses of these drugs than dogs do, so your veterinarian will adjust based on repeat testing [2][3]. - An adrenal crisis is a medical emergency. Severe weakness, collapse, or a slow or irregular heartbeat need care right away [4]. - Never stop or change adrenal medications on your own. Stopping suddenly can trigger a crisis. ## What Is Addison's Disease in Cats? Addison's disease, also called hypoadrenocorticism, happens when the adrenal glands stop producing enough hormones [4]. The two hormones that matter most here are glucocorticoids (mainly cortisol) and mineralocorticoids (mainly aldosterone) [1]. Cortisol helps the body handle stress, control blood sugar, and manage inflammation. Aldosterone controls sodium and potassium balance. When aldosterone drops, potassium builds up in the blood and sodium falls. In severe cases, that electrolyte imbalance can slow the heart or make it beat irregularly [4]. The disease is rare in cats. Only about 40 cases were documented in the 40 years after it was first described in 1983 [5]. Some cats lose only cortisol, some lose only aldosterone, and some lose both [1]. The mixed form is what most published feline cases describe [6]. There is also a separate problem on the opposite end of the spectrum: Cushing's disease, where the adrenal glands make too much cortisol. Cushing's disease in cats treatment usually involves medication that suppresses cortisol production, and it is managed very differently from Addison's. If your cat has been diagnosed with Cushing's, the drug plan, monitoring schedule, and risks are not the same as what you will read here. ## Signs Owners Notice First The signs of Addison's disease in cats are vague, and that is the main reason diagnosis gets delayed. They tend to come and go over days, weeks, or even months before anyone puts the pieces together [1][5]. Common signs include: - Loss of appetite and weight loss [4][2] - Lethargy and reduced general condition [4][2] - Dehydration [4][2] - Vomiting and diarrhea [4] - Constipation (obstipation) [2] - Weakness and low body temperature [2][7] Cats with abnormal sodium and potassium levels are more likely to be dehydrated, weak, or hypothermic on examination, and oddly, they are less likely to have a history of vomiting than cats with normal electrolytes [7]. Some cats show up in an adrenal crisis instead. That means sudden severe shock, collapse, or signs of kidney failure, and it can develop without much warning even if earlier signs seemed mild [4]. A few cats have unusual presentations. One report described a cat with atypical hypoadrenocorticism who came in having seizures from severely low blood sugar [6]. Another cat with the disease also had exocrine pancreatic insufficiency, low cobalamin, chronic gut disease, and later developed diabetes [8]. These are exceptions, but they show why Addison's can hide behind other problems. ## Causes and Risk Factors In most cats, the cause is not known, but an autoimmune process is likely. The body's immune system appears to destroy part of its own adrenal tissue [4]. When researchers examined the adrenal glands of one affected cat after death, they found lymphoplasmacytic adrenalitis with a T-cell rich infiltrate, which supports an autoimmune cause [8]. The adrenal glands can also be damaged by other conditions, including cancer elsewhere in the body [4]. Addison's disease has been reported in cats from 2 to 10 years old in one case series, with a median age of 6.5 years [2]. A larger report found a median age of 5.7 years, with a range from 2 months to 13.8 years [7]. Males made up 56% of that group and females 44% [7]. British Shorthair cats may be overrepresented, so veterinarians should be especially alert when this breed shows compatible signs [2][3]. One important look-alike: a low sodium to potassium ratio is not proof of Addison's. A young Maine Coon cat with severe hyperkalemia and hyponatremia turned out to have a Tritrichomonas foetus infection instead, and ACTH stimulation testing ruled out hypoadrenocorticism. Treating the parasite resolved the electrolyte problem [9]. ## How Addison's Disease Is Diagnosed Diagnosis starts with history, physical examination, and screening lab work: a complete blood count, chemistry panel, and urinalysis [1]. Your veterinarian is looking for electrolyte changes, especially low sodium and high potassium, along with other clues. The confirmation test is the ACTH stimulation test. A low resting cortisol with an inadequate or absent response to synthetic ACTH is diagnostic [5]. This test should be done before any glucocorticoid treatment starts, because steroids interfere with the results [3]. In stable cats, a baseline cortisol can be used as an initial screen, but the cutoff used in dogs (above 2 µg/dL, or 55 nmol/L, to rule out the disease) has not been validated in cats and should be interpreted with caution [3]. Some published testing protocols use three timed blood samples, which can be hard on a sick or stressed cat [5]. Your veterinarian will choose a protocol that fits your cat's condition and temperament. Imaging can add information. In one case series, the adrenal glands looked small on ultrasound in 6 of 11 cats [2]. ## Treatment Options for Feline Hypoadrenocorticism Management Treatment has two jobs: get your cat through a crisis if one is happening, and then keep hormones balanced for life. ### Emergency Treatment for an Addison's Crisis in Cats An adrenal crisis is treated in the hospital with intravenous fluids to correct dehydration and electrolyte imbalances, along with injectable hormone replacement. Cats in shock or with heart rhythm problems need continuous monitoring. This phase cannot be managed at home. ### Glucocorticoid Replacement Most cats need a daily glucocorticoid. Oral prednisolone is the typical choice for long-term management [3]. It replaces the cortisol the body is missing and helps your cat handle stress, eat normally, and feel well. Dosing is individual. Your veterinarian calculates the starting dose from your cat's weight and adjusts it based on how your cat responds and what repeat testing shows. Cats generally need higher maintenance doses than dogs [3]. In one study, the prednisolone maintenance dose used was 0.3 mg/kg per day, titrated to the individual cat [2]. ### Mineralocorticoid Replacement If aldosterone is low, your cat also needs a mineralocorticoid. Two options exist. **Desoxycorticosterone pivalate (DOCP)** is given by injection, usually about every 28 days. In one study of 11 cats, the starting DOCP dose was 2.2 mg/kg every 28 days, and requirements in cats were higher than what is typically used in dogs [2]. Your veterinarian sets the exact dose and interval for your cat. **Fludrocortisone** is an oral mineralocorticoid that some cats take instead. It is used in feline hypoadrenocorticism management, though published long-term feline data are limited. Your veterinarian will decide which option suits your cat and monitor accordingly. ### Supportive Care Some cats need extra support, especially at first. That can include treatment for dehydration, management of low blood sugar if it occurs, and care for any other conditions found along the way. One cat with multiple endocrine problems needed treatment for pancreatic insufficiency, cobalamin deficiency, and later diabetes [8]. If your cat is on steroids long term, it helps to understand how these drugs behave in cats. Our article on [Corticosteroid Therapy in Feline Diseases: Special Considerations](/knowledge/veterinary-medicine/clinical-pharmacology/corticosteroid-therapy-feline-diseases-special-considerations) explains the basics. | Treatment | What It Replaces | How It Is Given | Key Monitoring | |---|---|---|---| | Prednisolone | Glucocorticoid (cortisol) | Oral, daily | Appetite, energy, stress response, dose adjustment [2][3] | | DOCP | Mineralocorticoid (aldosterone) | Injection, about every 28 days | Sodium, potassium, dose interval [2] | | Fludrocortisone | Mineralocorticoid (aldosterone) | Oral, daily | Sodium, potassium, blood pressure | | IV fluids and injectable steroids | Both, in a crisis | In hospital | Electrolytes, heart rhythm, hydration [4] | ## Recovery, Outlook, and Long-Term Management The outlook for cats with Addison's disease is generally good when treatment is consistent. Treatment is highly successful but often lifelong [1]. In one case series, 8 cats were followed for 14 to 70 months, with a median follow-up of 28 months [2]. That tells you many cats do well for years with proper care. Long-term management means: - Giving medication every day, at the same times, without skipping. - Keeping routine recheck appointments, even when your cat seems fine. - Expecting dose adjustments over time. Cats' requirements can change, and DOCP intervals may need fine-tuning [2]. - Watching for stress. Illness, surgery, and travel can raise hormone needs, so ask your veterinarian whether the dose needs a temporary bump. - Telling every veterinarian your cat sees that your cat has Addison's disease. Some cats have other conditions alongside Addison's, which can affect the overall outlook. The cat in one report developed diabetes and was euthanized 10 months after diagnosis because of status epilepticus unrelated to glucose or electrolyte problems [8]. That is a single case, not a typical outcome, but it shows why ongoing veterinary care matters. If your cat also has an overactive thyroid, treatment decisions get more complex. Our guide to [Cat Hyperthyroidism: What to Expect from Treatment Options and Costs](/knowledge/veterinary-medicine/senior-and-chronic-care/cat-hyperthyroidism-treatment-costs) covers what that management involves. The opposite problem, an underactive thyroid, is covered in [Cat Hypothyroidism: Symptoms, Diagnosis, and Treatment Options](/knowledge/veterinary-medicine/senior-and-chronic-care/cat-hypothyroidism-symptoms-treatment). ## Prevention There is no known way to prevent Addison's disease in cats. The likely autoimmune cause means it is not something you can head off with diet, lifestyle, or vaccines [4]. What you can do is reduce the risk of a crisis: - Get vague signs checked early. Lethargy, appetite loss, and vomiting that come and go deserve a veterinary visit [1]. - Do not skip doses. Missing medication is one of the most common reasons cats crash. - Ask about stress dosing before surgery, boarding, or any major change. - Keep electrolyte checks on schedule, since problems can build before your cat looks sick [4]. ## Limitations and When to Contact a Veterinarian Every cat with Addison's disease is different, and dosing, monitoring intervals, and emergency plans need to be set by your veterinarian for your individual cat. Call your veterinarian the same day if your cat: - Refuses food for more than 24 hours - Vomits repeatedly or has diarrhea that will not stop - Seems weak, wobbly, or unusually quiet - Misses one or more doses of medication Go to an emergency clinic now if your cat: - Collapses or cannot stand - Breathes fast or seems to be in shock - Has a very slow or irregular heartbeat [4] - Has a seizure Routine visits matter too. Even a cat who looks completely normal needs periodic blood work to check sodium, potassium, and overall health, because dose needs can shift quietly over time [2]. ## Frequently Asked Questions ### Can Addison's disease in cats be cured? No, it cannot be cured, but it can be managed very well. Most cats need hormone replacement for life, and treatment is highly successful in the great majority of cases [1]. With consistent medication and monitoring, many cats live normal lifespans. ### How often will my cat need blood tests? It varies with how stable your cat is. Right after diagnosis, testing is frequent while doses are adjusted. Once your cat is stable, rechecks are usually spaced out over months. Your veterinarian will set the schedule based on your cat's electrolytes, medication type, and overall condition. ### Is fludrocortisone or DOCP better for cats? There is no clear winner in the veterinary literature, because feline cases are so rare. DOCP has more published long-term feline data, including specific dosing information [2]. Fludrocortisone is an oral alternative that some cats take daily. Your veterinarian will pick based on your cat's response, your ability to give injections, and cost. ### What happens if I miss a dose? A single missed dose may not cause problems, but repeated missed doses can lead to a crisis. Call your veterinarian for guidance on what to do, and never double up unless you are told to. If your cat becomes weak or collapses after a missed dose, treat it as an emergency [4]. ### Do cats with Addison's disease need a special diet? No specific diet is proven to treat Addison's disease in cats. The priority is that your cat eats reliably, since appetite loss is a common sign of trouble [4]. If your cat has other conditions, such as kidney or gut disease, your veterinarian may recommend a targeted diet for those problems instead. ## Related Articles - [Cat Hypothyroidism: Symptoms, Diagnosis, and Treatment Options](/knowledge/veterinary-medicine/senior-and-chronic-care/cat-hypothyroidism-symptoms-treatment) - [Flea Treatment For Cats](/knowledge/veterinary-medicine/parasitic-diseases/flea-treatment-for-cats) - [Corticosteroid Therapy in Feline Diseases: Special Considerations](/knowledge/veterinary-medicine/clinical-pharmacology/corticosteroid-therapy-feline-diseases-special-considerations) - [Cat Hyperthyroidism: What to Expect from Treatment Options and Costs](/knowledge/veterinary-medicine/senior-and-chronic-care/cat-hyperthyroidism-treatment-costs) - [Addisons Disease in Dogs: Hypoadrenocorticism Crisis Electrolyte Balance](/knowledge/veterinary-medicine/internal-medicine/addisons-disease-in-dogs-hypoadrenocorticism-crisis-electrolyte-balance) - [What Is The Treatment For Cat Scratch Disease](/knowledge/veterinary-medicine/clinical-methods/what-is-the-treatment-for-cat-scratch-disease) ## References 1. [Addison Disease (Hypoadrenocorticism) in Animals - Endocrine System](https://www.merckvetmanual.com/endocrine-system/the-adrenal-glands/addison-disease-hypoadrenocorticism-in-animals). Merck Veterinary Manual. 2. [Clinical features and long-term management of cats with primary hypoadrenocorticism using desoxycorticosterone pivalate and prednisolone](https://pubmed.ncbi.nlm.nih.gov/36809682/). Journal of veterinary internal medicine, 2023. 3. [Feline hypoadrenocorticism: Emerging insights into clinical features, diagnosis, and treatment](https://pubmed.ncbi.nlm.nih.gov/42411116/). Schweizer Archiv fur Tierheilkunde, 2026. 4. [Disorders of the Adrenal Glands in Cats - Cat Owners](https://www.merckvetmanual.com/cat-owners/hormonal-disorders-of-cats/disorders-of-the-adrenal-glands-in-cats). Merck Veterinary Manual. 5. [Hypoadrenocorticism in cats: a 40-year update](https://pubmed.ncbi.nlm.nih.gov/39325772/). Journal of feline medicine and surgery, 2024. 6. [Successful treatment of atypical hypoadrenocorticism in a cat presenting with hypoglycaemic seizures](https://pubmed.ncbi.nlm.nih.gov/40161866/). JFMS open reports, 2025. 7. [Clinical findings, treatment, and outcomes in cats with naturally occurring hypoadrenocorticism: 41 cases](https://pubmed.ncbi.nlm.nih.gov/39660757/). Journal of veterinary internal medicine, 2025. 8. [Histopathological evaluation of the adrenal glands in a cat with primary hypoadrenocorticism and multiple endocrine disease](https://pubmed.ncbi.nlm.nih.gov/36226303/). JFMS open reports, 2022. 9. [Hypoadrenocorticism-like syndrome in a cat with Tritrichomonas foetus infection: a case report](https://pubmed.ncbi.nlm.nih.gov/41656001/). The Journal of small animal practice, 2026. ## Further Reading - [American Veterinary Medical Association: First Aid Tips for Pet Owners](https://www.avma.org/resources-tools/pet-owners/emergencycare/first-aid-tips-pet-owners) - [Merck Veterinary Manual: Cat Owners](https://www.merckvetmanual.com/cat-owners) - [Cornell Feline Health Center: Health Information](https://www.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information)