# Eclampsia in Cats: Symptoms, Risks, and Emergency Care Cat eclampsia symptoms appear when a nursing mother cat's blood calcium drops too low, most often during peak milk production. The signs start subtly with restlessness, tremors, or a stiff, unsteady walk, then can progress to seizures and collapse within hours. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Quick Answer - Eclampsia (periparturient hypocalcemia) is a calcium emergency in nursing queens, and it can move from mild tremors to seizures and death if untreated [1]. - Call your veterinarian or an emergency clinic the moment you see tremors, stiffness, panting, or disorientation in a cat that recently gave birth or is nursing. - Do not wait to see if it passes. Neurologic signs in eclampsia are progressive, meaning they get worse without treatment [1]. - Diagnosis is based on the cat's history and signs, and confirmed by measuring serum calcium [1]. - Treatment is veterinary only. Your vet calculates the calcium dose from your cat's weight and health, so never attempt home treatment. ## What Is Eclampsia in Cats? Eclampsia is the medical term for a dangerous drop in blood calcium around the time of birth and nursing. In cats, it is also called periparturient hypocalcemia or postpartum eclampsia. The word "periparturient" simply means around the time of giving birth. Calcium does far more than build strong bones. It helps nerves fire, muscles contract, and the heart beat in a steady rhythm. When calcium falls too low, the nervous system becomes overexcitable. That is why the first signs are often twitching, tremors, and muscle stiffness. As calcium drops further, the brain and heart are affected, and the situation becomes life threatening. Eclampsia is well described in small animals, and the classic picture is a small mother nursing a large litter at peak lactation [1]. In dogs, that peak is usually two to three weeks after whelping [1]. Cats follow a similar pattern, though the timing can vary. Some queens show signs earlier, and hypocalcemia can even occur during labor and contribute to a difficult birth [1]. One important point for cat owners: low calcium is not always caused by nursing. Cats with kidney disease, certain cancers, and other serious illnesses can also develop hypocalcemia. In a large review of azotemic cats and dogs, ionized hypocalcemia was mild in most cats but moderate in about 23% and severe in a small number [2]. That tells us calcium problems show up in many sick cats, not only nursing mothers. ## Signs of Eclampsia in Cats The earliest signs are easy to miss because they look like ordinary mothering behavior or mild stress. A queen may seem restless, pace, or pant. She might hold her head oddly or have fine muscle twitches in her face and legs. As calcium falls, the signs become more obvious: - Tremors or shivering that does not stop - Muscle stiffness, a rigid stance, or a stiff-legged walk - Unsteady gait or wobbliness (ataxia) - Disorientation, staring, or not responding normally to her kittens - Panting or rapid breathing without obvious heat or exertion - Drooling, lip smacking, or facial twitching - Weakness, reluctance to stand, or collapse - Seizures, which are a late and severe sign The Merck Veterinary Manual describes eclampsia as progressive neurologic signs including tremors, ataxia, and disorientation, eventually followed by seizures, coma, and death [1]. That progression is the reason this condition is treated as an emergency. The window between "a little shaky" and "seizing" can be short. Panting deserves special attention. A nursing cat who pants may be overheated, stressed, or in pain, but in a postpartum queen it can also be an early eclampsia sign. If panting comes with tremors, stiffness, or a change in behavior, treat it as urgent. Breathing problems in cats are always serious, and you can read more about warning signs in our guide to [cat difficulty breathing](/knowledge/veterinary-medicine/online-vet-and-care-costs/cat-difficulty-breathing-emergency). ### Cat Pre Eclampsia: Does It Exist? Some owners search for "cat pre eclampsia," meaning a warning phase before full eclampsia. In practice, the early signs of hypocalcemia are the warning phase. There is no separate, well-defined condition called preeclampsia in cats the way there is in people. If your cat is showing tremors, stiffness, or unusual behavior after giving birth, she is already in the danger zone and needs veterinary attention now. ## Causes and Risk Factors The main driver of eclampsia is the calcium demand of milk production. A nursing queen loses calcium into her milk every time she feeds her kittens. If her body cannot pull enough calcium from her bones and diet fast enough, blood calcium falls. Risk factors include: - Nursing a large litter - Small body size, which means less calcium reserve - First-time mothers, who may not regulate calcium as efficiently - Poor nutrition during pregnancy, especially diets low in calcium or unbalanced in phosphorus - Peak lactation, which in dogs is two to three weeks after birth [1] - Difficult or prolonged labor, since hypocalcemia can occur during parturition and may contribute to dystocia [1] Beyond nursing, other causes of low calcium in cats include kidney disease, certain tumors, and critical illness. A case report described a cat with a parathyroid chief cell carcinoma that caused high calcium, not low, which shows how tightly the parathyroid glands control calcium balance [3]. In sick cats, ionized hypocalcemia is common and often mild, but it can be moderate or severe [2]. If your cat has kidney problems, ask your vet whether calcium should be monitored. Some cats with urinary blockage also develop electrolyte and calcium abnormalities. If your cat is straining to urinate, that is a separate emergency, and you can learn more in our article on a [cat straining to pee](/knowledge/veterinary-medicine/symptom-guides/cat-straining-to-pee). ## How Eclampsia Is Diagnosed Diagnosis starts with the story you tell your veterinarian. A recently pregnant or nursing cat with tremors, stiffness, or panting is a strong clue. Vets call this a presumptive diagnosis based on signalment (age, sex, reproductive status) and clinical signs [1]. Confirmation requires measuring the serum calcium concentration [1]. A blood sample is drawn and sent to a lab, or run on an in-house analyzer. Total calcium and ionized calcium can both be measured. Ionized calcium is the active form, and it is the value used in many emergency settings. Your vet may also run: - A blood glucose check, since low blood sugar can cause similar tremors - Electrolytes including magnesium, because magnesium disturbances often travel with calcium problems [4] - Kidney values, to rule out kidney disease as a cause - A physical exam and temperature check In one study of dogs and cats with septic peritonitis, ionized calcium and magnesium disturbances were linked to heart arrhythmias, gastrointestinal ileus, and blood clotting problems [4]. That study is about a different condition, but it reinforces a simple truth: calcium and magnesium matter for the whole body, and vets often check both. ### What the Blood Test Shows A low total or ionized calcium value confirms hypocalcemia. The degree of the drop helps your vet judge severity. In azotemic cats, most low calcium readings were mild, but about 23% were moderate and a small number were severe [2]. Severe hypocalcemia is the group most likely to cause seizures and heart problems. ## Treatment Options Eclampsia treatment is veterinary and usually urgent. The cornerstone is replacing calcium under close supervision. Calcium is given intravenously in a controlled way, because giving it too fast can cause dangerous heart rhythm problems. Your vet calculates the exact dose from your cat's weight and health, and the rate is adjusted based on monitoring. Supportive care often includes: - Intravenous fluids to support circulation - Warming if the cat is hypothermic - Oxygen if breathing is labored - Anti-seizure medication if seizures are ongoing - Oral calcium supplementation once the crisis is controlled, with a dose your vet calculates The kittens need attention too. If the queen cannot nurse safely, the kittens must be hand-fed or fostered. A veterinarian or veterinary technician can show you how to bottle-feed if needed. Never give your cat human calcium supplements, antacids, or bone meal on your own. The dose and form matter, and too much calcium causes its own serious problems. Your vet will tell you exactly what to give and how much. ## Recovery, Outlook, and Long-Term Management Most cats improve quickly once calcium is replaced. Tremors and stiffness often ease within minutes to hours of treatment. Full recovery depends on how low the calcium dropped, how long the cat was affected, and whether there are other illnesses. After the crisis, your vet will likely recommend: - Oral calcium supplementation for a period of time - Reducing the calcium drain by supplementing the kittens' feeding or weaning earlier - A balanced, high-quality diet for the queen - Recheck blood calcium levels to make sure the dose is right - Spaying if the cat should not have more litters Recurrence is possible in future pregnancies, especially in cats who had a severe episode. If you plan to breed your cat again, talk with your vet first about a prevention plan. ## Prevention Prevention focuses on nutrition and monitoring. Feed a complete and balanced diet formulated for pregnancy and lactation. Do not add random calcium supplements during pregnancy, because this can actually disrupt the body's natural calcium regulation. Ask your vet before adding anything to the diet. Watch nursing queens closely during the first three weeks after birth, which is peak lactation in dogs and a high-risk window in cats too [1]. Know the early signs so you can act fast. If your cat had eclampsia before, tell your vet before any future pregnancy. Your vet may recommend monitoring calcium levels or adjusting the feeding plan. In many cases, the safest choice is to spay and avoid another pregnancy. ## Limitations and When to Contact a Veterinarian This article gives general information. Every cat is different, and individual cases need a veterinarian who can examine your cat and run tests. Call an emergency clinic right now if your cat has: - Seizures or convulsions - Collapse or inability to stand - Severe tremors or whole-body stiffness - Labored breathing, open-mouth breathing, or blue gums - A temperature that feels very high or very low Call your veterinarian the same day if your nursing cat has: - Fine tremors, twitching, or shivering - Panting without a clear cause - Stiffness, wobbliness, or an odd gait - Disorientation or unusual behavior - Drooling or facial twitching Schedule a routine visit if your cat had eclampsia in the past and you are planning another pregnancy, or if you want to review her diet and calcium needs. If your cat has kidney disease or another chronic illness, ask whether calcium should be part of routine monitoring, since hypocalcemia is common in azotemic cats [2]. ## Frequently Asked Questions ### How fast can eclampsia become dangerous in a cat? It can become dangerous within hours. The neurologic signs are progressive, so tremors can advance to seizures, coma, and death if calcium is not replaced [1]. Treat any tremor or stiffness in a nursing queen as an emergency. ### Can a cat have eclampsia before giving birth? Yes, hypocalcemia can occur during parturition. Low calcium at that time may contribute to a difficult birth, also called dystocia [1]. If a cat in labor seems weak, shaky, or unable to deliver, contact your vet right away. ### Is panting always a sign of eclampsia in a nursing cat? No, panting has many causes, including heat, stress, and pain. But in a postpartum queen, panting combined with tremors, stiffness, or behavior changes points toward eclampsia. When in doubt, call your vet. ### Can I treat my cat's low calcium at home? No. Calcium replacement for eclampsia must be given under veterinary supervision because rapid or incorrect dosing can cause heart rhythm problems. Your vet calculates the dose from your cat's weight and health, and oral supplements are added only after the crisis is controlled. ### Will my cat need to stop nursing her kittens? Often yes, at least temporarily. Reducing the calcium drain is part of treatment, so your vet may recommend supplementing the kittens' feeding or weaning earlier. The kittens can be hand-fed or fostered while the queen recovers. ## Related Articles - [Cat Difficulty Breathing: Emergency Signs and What to Do](/knowledge/veterinary-medicine/online-vet-and-care-costs/cat-difficulty-breathing-emergency) - [Cat Straining to Pee: Is It an Emergency?](/knowledge/veterinary-medicine/symptom-guides/cat-straining-to-pee) - [Cat Urinary Infection Symptoms](/knowledge/veterinary-medicine/symptom-guides/cat-urinary-infection-symptoms) - [Electrolyte Emergencies in Dogs and Cats: Recognition and Correction](/knowledge/veterinary-medicine/emergency-critical-care/electrolyte-emergencies-dogs-cats-recognition-correction) - [Symptoms Of Urinary Infection Cats](/knowledge/veterinary-medicine/symptom-guides/symptoms-of-urinary-infection-cats) - [What Are Symptoms Of A Uti In A Cat](/knowledge/veterinary-medicine/symptom-guides/what-are-symptoms-of-a-uti-in-a-cat) - [Can Milk Fever Kill a Cat? Eclampsia Signs and Treatment](/knowledge/veterinary-medicine/emergency-and-first-aid/milk-fever-cats-fatal) - [Eclampsia in Cats: Symptoms, Treatment, and Recovery](/knowledge/veterinary-medicine/emergency-and-first-aid/cat-eclampsia-treatment) - [Eclampsia in Dogs: Symptoms, Treatment, and Prevention](/knowledge/veterinary-medicine/emergency-and-first-aid/eclampsia-dogs-symptoms-treatment) ## References 1. [Eclampsia in Small Animals - Metabolic Disorders](https://www.merckvetmanual.com/metabolic-disorders/disorders-of-calcium-metabolism/eclampsia-in-dogs-and-cats). Merck Veterinary Manual. 2. [Severity, etiology and outcomes of ionized hypocalcemia in azotemic cats and dogs](https://pubmed.ncbi.nlm.nih.gov/42382116/). Frontiers in veterinary science, 2026. 3. [A case of suspected ectopic parathyroid chief cell carcinoma in a cat](https://pubmed.ncbi.nlm.nih.gov/41905940/). The Journal of veterinary medical science, 2026. 4. [Ionized calcium and ionized magnesium disturbances in dogs and cats with septic peritonitis](https://pubmed.ncbi.nlm.nih.gov/40454174/). Frontiers in veterinary science, 2025. ## 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)