Addison’s Disease in Dogs: Signs, Diagnosis, and Management

Addison's disease is called the great pretender for a reason — its signs are vague and come and go, so it's often missed until a dog gets seriously unwell. Knowing the pattern can change the outcome.

Addison's disease (hypoadrenocorticism) is a condition where a dog's adrenal glands don't make enough of certain hormones, causing vague, waxing-and-waning signs like lethargy, poor appetite, vomiting, and weakness. It's diagnosed by your veterinary team with specific blood tests, and it's manageable long-term with medication a vet prescribes and monitors. An Addisonian crisis is an emergency.

The "great pretender" — and why that's dangerous

Addison's earns its nickname : the signs (lethargy, poor appetite, vomiting, weakness) come and go and mimic a dozen other things, so it's frequently missed until a dog collapses in an Addisonian crisis. Knowing the waxing-and-waning pattern — a dog that gets sick, seems to recover, then relapses, often under stress — is what gets it caught before the crisis.

The crisis is a true emergency

An Addisonian crisis — sudden collapse, severe weakness, sometimes shock — is life-threatening and needs emergency veterinary care immediately. It often strikes during stress (travel, boarding, illness). If a known or suspected Addison's dog crashes, treat it as the emergency it is.

Diagnosis and outlook

Specific blood tests confirm it; vague signs alone can't. The genuinely good news, and the counterweight to the scary parts: once diagnosed, Addison's is very manageable with hormone-replacement medication and monitoring, and most dogs go on to live normal lives. It's one of the more treatable chronic conditions once it's found.

Long-term management

It's managed with medication like desoxycorticosterone (Zycortal) plus monitoring, directed by your vet. We never set doses; that's the clinical team's role.

About Zycortal (DOCP) for Addison's: this is a prescription medication your veterinarian can prescribe. Read our guide, or ask us if you need help sourcing it.

What Addison's disease is

The adrenal glands sit near the kidneys and make hormones that regulate salt, water, and stress response. In Addison's, they under-produce, which throws off the body's balance. It most often affects young to middle-aged dogs, and some breeds are more prone. ^[1]

The signs (and why they're missed)

Lethargy, reduced appetite, vomiting, diarrhea, weight loss, and weakness — all of which come and go, and all of which fit many other conditions. That vagueness is exactly why Addison's is often diagnosed late, sometimes only during a sudden crisis. ^[2]

Diagnosis and long-term management

Diagnosis relies on specific blood tests your veterinarian runs. Once confirmed, Addison's is managed long-term with hormone-replacement medication — such as desoxycorticosterone pivalate (Zycortal) — prescribed and monitored by your vet. With proper management, most dogs do very well. We never set doses; your veterinary team does.

Frequently asked questions about addison’s disease in dogs

For educational use. PrepperPetSupply is a licensed, veterinarian-staffed pharmacy; prescriptions are dispensed only after review by a licensed veterinarian and are not a substitute for in-person veterinary care. Not for human use.