Emergency — phone the vet now Within hours

Addisonian crisis in dogs

Sudden weakness, vomiting, and collapse in a young-to-middle-aged dog can be Addison's crisis — phone the vet now; this is life-threatening but very treatable.

Dog

Recognise the signs

  • Episodic weakness, vomiting, diarrhoea, often improving with rest then recurring
  • Sudden severe collapse with weakness
  • Slow heart rate
  • Pale gums
  • Often misdiagnosed as gut upset before crisis

First aid steps

  1. Phone the emergency vet.
  2. Mention 'possible Addisonian crisis' especially in known cases.

Do NOT

  • Do not give human medications.
  • Do not delay in known Addisonian on stress events.

While transporting to the vet

  • Bring records of any current steroid use.

When to phone the vet immediately

  • Any collapse with vomiting and weakness
  • Known Addisonian during stress

Common causes

  • Underactive adrenal glands (primary Addison's)
  • Stopping long-term steroids abruptly (secondary)
  • Often unmasked by stress events

What the vet will need to know

  • Recent steroid history
  • Stress events (kennelling, surgery, travel)
  • Episode pattern

Aftercare

  • Hospitalisation with IV fluids and steroid replacement.
  • Lifelong DOCP (or fludrocortisone) and oral steroid replacement.
  • Stress-dose adjustment for procedures and stress events.
  • Excellent prognosis with proper treatment.

Prevention

  • Never stop long-term steroids abruptly.
  • Communicate Addisonian status before any procedure.
  • Stress-dose protocol from vet for known events.

Breed-specific notes

  • Higher risk: Standard Poodle, Bearded Collie, Portuguese Water Dog, Wheaten Terrier, Great Dane.

Frequently asked questions

Why is Addison's called 'the great pretender'?

Episodic vague symptoms mimic gut upset, kidney issues, or general malaise — easily missed until crisis. Vet bloodwork during a flare-up gives the diagnosis.

Can my dog live a normal life with Addison's?

Yes — with daily medication and stress-dose protocols, most have an essentially normal lifespan and quality of life.

Is it expensive to treat?

Monthly DOCP injections and daily prednisolone are moderate ongoing costs. Pet insurance helps, particularly bought before any episode.

Animal PoisonLine 01202 509 000 Emergency
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