Eclampsia in Dogs and Cats: Signs and Emergency Treatment

By Dr Duncan Houston

A nursing dog who suddenly pants, paces or walks stiffly needs prompt attention. A nursing cat may instead seem weak, stop eating or develop trembling.

These changes can signal eclampsia, a calcium emergency. Recognising the early change matters more than waiting for a dramatic seizure.

Quick Answer

Eclampsia is a dangerous fall in blood calcium, usually associated with milk production after birth. Suspected eclampsia needs immediate veterinary care: stop the litter suckling and call your vet or an emergency clinic. Do not try to correct it with milk, antacids or calcium injections at home. Prompt treatment often produces a good response, but the mother and litter need a continuing care plan.

Why does eclampsia happen?

Milk production creates a large calcium demand. If the mother's body cannot keep blood calcium at a safe level, nerve and muscle function becomes disturbed. Eclampsia is also called milk fever or puerperal tetany.

It most often develops in the first few weeks of nursing, although it can occur before birth. Small dogs are more susceptible. This background raises suspicion, but a larger dog with compatible signs still needs assessment. See VCA's veterinary explanation of canine eclampsia.

Cats can develop eclampsia too, although it is uncommon. Affected cats may have poor appetite, lethargy, trembling, pale gums or abnormal breathing. Some have a low body temperature, so absence of fever is not reassuring. A large nursing litter increases concern. VCA describes the different signs in cats.

Which signs change the urgency?

What you notice	Why it matters	What to do
New unexplained panting, pacing, poor appetite or unusual weakness during nursing	Early signs may be subtle and have several causes	Call your vet now for triage. Do not leave a changing or unwell mother until morning.
Trembling, muscle twitching, stiff steps or trouble standing	Possible calcium-related muscle dysfunction	Arrange emergency assessment immediately and prevent suckling.
Seizure, collapse or difficulty breathing	Critical illness, whatever the cause	Contact the emergency clinic and leave for care immediately.

The table is an action guide, not a way to diagnose calcium levels. There is no safe home observation period for suspected eclampsia.

What else could cause these signs?

A nursing mother can be ill for reasons other than calcium loss. The vet considers the whole examination, including her milk glands, rather than assuming every postpartum change is eclampsia.

Mastitis: painful, swollen or discoloured milk glands, abnormal milk and a mother who feels unwell suggest mammary inflammation or infection. It affects dogs and cats and can become serious.
Other metabolic or neurological problems: blood glucose disturbances, toxins and diseases affecting the brain or other organs can cause seizures. Veterinary guidance on seizures in dogs and cats explains why investigations include a history, examination and blood tests.
Other causes of low calcium: kidney, pancreatic or parathyroid disease may need consideration when the history or results do not fit lactation-related eclampsia. VCA explains the assessment of hypocalcemia.

When is this an emergency?

Suspected eclampsia is already an emergency, even before seizures start. Do not wait for every sign in the table or for a home remedy to work.

Call while arranging transport. Say that your dog or cat is pregnant or nursing, describe the signs and tell the clinic when they began.
Prevent the puppies or kittens from suckling. Arrange safe, warm care for them and ask the clinic whether to bring them. Their feeding needs must be addressed promptly.
Protect a seizing mother from injury. Clear nearby objects, keep her away from stairs and keep hands and objects out of her mouth. Do not force food, water or tablets into her mouth.
Bring useful information. Take food and supplement labels and note the birth date, litter size, recent medicines and possible toxin exposure. Do not delay departure to make a detailed record.

How do vets confirm and treat eclampsia?

The vet assesses breathing, circulation, temperature and muscle activity, then checks blood calcium alongside other relevant tests. Ionized calcium measures the biologically active fraction. Total calcium can be affected by blood protein levels, so the number needs clinical interpretation. VCA's explanation of calcium testing describes this distinction.

Emergency treatment generally involves calcium given slowly into a vein, with close heart monitoring. Giving it too quickly can cause dangerous heart rhythm changes. Additional treatment may be needed for seizures or other abnormalities. This is why veterinary calcium treatment requires careful administration.

Improvement can be rapid, but looking better does not mean treatment is finished. Before discharge, obtain written instructions for any prescribed oral calcium, follow-up checks and nursing restrictions. Use the exact preparation and dose the clinic specifies. If concerning signs return, contact the clinic immediately instead of adjusting the dose yourself.

What happens to the puppies or kittens?

The vet will decide whether nursing can resume or whether supplementary feeding or weaning is needed. The decision depends on the mother's condition and the litter's age and ability to feed. Stopping suckling during the emergency does not mean young animals can immediately manage on solid food.

Ask for a species-appropriate milk replacement and feeding plan, including a demonstration if hand feeding is necessary. Cow's milk is not an appropriate replacement. Track each youngster's weight and report poor feeding or failure to gain. These principles are covered in veterinary guidance on puppy care through weaning and feeding kittens without their mother's milk.

Also ask how to monitor the mother's milk glands after nursing stops. Milk accumulation can contribute to mastitis; painful swelling or discolouration warrants veterinary advice. Do not restart nursing or begin expressing milk without discussing the plan.

Common mistakes to avoid

Assuming shaking is simply tiredness from caring for a litter.
Waiting for a seizure before seeking help.
Using an online calcium dose or choosing a human antacid yourself.
Restarting unrestricted nursing as soon as the mother seems brighter.
Separating the litter without arranging warmth, feeding and weight monitoring.

Can you reduce the risk?

Arrange a nutrition plan before birth. Feed a complete diet appropriate for pregnancy and lactation in the correct species, with portions adjusted to body condition and litter demands. Ask your vet to check the food's suitability rather than relying on the words “puppy” or “kitten” alone. Veterinary nutrition guidance is available for pregnant and nursing dogs and pregnant and nursing cats.

Do not add calcium during pregnancy unless your vet specifically directs it. Excess supplementation can interfere with normal calcium regulation. Tell your vet about any previous eclampsia and every supplement you use; a prescribed treatment plan after diagnosis is different from routine preventive supplementation.

Keep food and fresh water accessible, monitor the mother's appetite and arrange individual postpartum follow-up. Nutrition and planning help, but they cannot guarantee that eclampsia will not develop.

Frequently asked questions

Can eclampsia happen before birth?

Yes. It is more often associated with nursing, but a pregnant dog or cat with trembling, weakness or seizures also needs urgent assessment.

Can I give calcium tablets while travelling to the vet?

Only if the treating vet specifically instructs you. Do not delay transport or force anything by mouth into an animal who is trembling severely, seizing or not swallowing normally.

Does milk fever always cause a high temperature?

No. The name can be misleading, and affected cats may have a low temperature. Judge urgency by the mother's condition, not whether she feels hot.

Will she recover completely?

Promptly treated animals often do well. The vet will assess her individual outlook and explain how to manage feeding and follow-up after stabilisation.

The decision that matters most

If a pregnant or nursing mother develops concerning muscle, movement or breathing changes, seek veterinary help immediately. Protecting her also protects her litter.

ASK A VET™ supports informed care for mothers and their litters. For suspected eclampsia, contact your treating vet or emergency clinic directly.