CONDITION

Eclampsia in Dogs

Eclampsia is a condition in which calcium levels in the blood drop rapidly, typically in the weeks following birth when a dog is nursing puppies. The body's demand for calcium can outpace what is available in circulation, and this imbalance affects how nerves and muscles function. Owners often notice restlessness, panting, or muscle tremors that appear suddenly in a nursing dog. Some dogs become unsteady or disoriented. The signs can progress quickly, and the presentation tends to be more striking in smaller dogs or those nursing large litters, though it can occur in any lactating dog. This page explores what the early signals of eclampsia can look like, the mechanism by which calcium depletion affects the body, how the condition is investigated, and the range of approaches used to address it.

Why this matters now

Eclampsia occurs almost exclusively in lactating dogs, most commonly in the first three to four weeks after whelping when milk production is at its peak. Smaller breeds tend to be affected more frequently, though the condition can develop in any nursing dog. Dogs with large litters face greater calcium demands, and those who were not supplemented with calcium during pregnancy may have depleted reserves by the time lactation begins.

The onset tends to be sudden, often appearing over the course of hours rather than days. Early restlessness or mild tremors can escalate to more pronounced muscle rigidity, incoordination, or altered awareness within a short window. The trajectory varies between individuals; some dogs show a slow build of subtle signs, whilst others present with little warning.

Signals & patterns

Early signals

Restlessness and pacing

A nursing dog may appear unable to settle, moving between resting spots or circling without clear purpose. This behaviour often emerges abruptly and persists despite attempts to comfort.

Panting without exertion

Rapid, shallow breathing may begin even in a cool environment or after minimal activity. The panting can seem disproportionate to the dog's recent movement or the ambient temperature.

Mild muscle tremors

Fine, rhythmic shaking may be visible in the limbs or face, sometimes described as a quivering or twitching. These tremors often worsen with handling or excitement.

Reduced interest in puppies

A dog who previously nursed attentively may begin to avoid the litter or seem distracted during feeding. This shift in maternal behaviour can be subtle at first.

Later signals

Stiff or unsteady gait

Movement may become rigid or clumsy, with the dog appearing to walk on stiff legs or stumble. Some dogs hold their limbs in an extended or awkward posture.

Disorientation or confusion

The dog may seem unaware of her surroundings, fail to recognise familiar people, or stand motionless staring into space. Responsiveness to voice or touch may diminish.

Generalised muscle spasms

Larger, involuntary contractions can affect the whole body, sometimes with the dog lying on her side and paddling or appearing unable to stand. These episodes may come in waves.

Click to read about the biological mechanisms

How this is usually investigated

The investigation typically begins with a clinical history that focuses on lactation status, litter size, and the timing and nature of the signs. Physical examination often reveals tremors, muscle rigidity, elevated heart rate, or altered responsiveness. Blood testing is used to measure calcium levels directly, and this result usually clarifies the picture when the clinical context fits.

Clinical history and observation

Purpose: The presence of lactation, the sudden onset of tremors or restlessness, and the timing in relation to whelping all point towards eclampsia. Observing the dog's gait, muscle tone, and mental state provides immediate context.
Considerations: The clinical picture can resemble other causes of tremor or altered mentation, so history alone does not confirm the diagnosis. Some dogs present with subtle early signs that may not be obvious during a brief examination.

Blood biochemistry

Purpose: A blood sample is analysed to measure total calcium, and often ionised calcium, which is the biologically active fraction. Low ionised calcium in a lactating dog with compatible signs supports the diagnosis.
Considerations: Calcium levels can fluctuate, and a single measurement reflects the moment the sample was taken. Some laboratories measure only total calcium, which can be affected by albumin levels and may not fully represent the available calcium pool.

Blood glucose measurement

Purpose: Glucose is often checked at the same time because low blood sugar can produce overlapping signs such as tremor, weakness, or altered behaviour. This test helps distinguish eclampsia from hypoglycaemia or concurrent metabolic disturbances.
Considerations: Normal glucose does not rule out eclampsia, and some dogs may have mild glucose changes secondary to stress or reduced food intake. The test is quick but requires a fresh sample for accuracy.

Physical examination findings

Purpose: Palpation may reveal muscle fasciculations, stiffness, or an elevated body temperature. Heart rate and respiratory rate are often increased, and some dogs show dilated pupils or hypersensitivity to sound or touch.
Considerations: These findings are not unique to eclampsia and can appear in other conditions affecting the nervous system or metabolism. The examination provides supporting detail rather than a definitive answer on its own.

Options & trade-offs

Management of eclampsia usually involves restoring blood calcium levels and reducing the immediate demand for calcium through milk production. The approach taken depends on the severity of signs, the owner's capacity to monitor the dog closely, and the practical options for managing the litter. Different combinations suit different households and different stages of the condition.

Intravenous calcium supplementation

Calcium is administered slowly through a vein, often as calcium gluconate, whilst the heart rate is monitored. The effect can be rapid, with tremors and rigidity subsiding within minutes to hours. The infusion is given carefully because calcium delivered too quickly can disturb heart rhythm.

Trade-offs: This approach requires access to a clinical setting and monitoring equipment. The effect is temporary if the underlying drain on calcium continues, so further supplementation or adjustments to lactation may be needed. Some dogs experience a recurrence if the litter continues to nurse without modification.

Oral calcium supplementation

Once the acute phase has been managed, calcium can be given by mouth to maintain blood levels whilst lactation continues or until the puppies are weaned. The dose and frequency are adjusted based on the dog's size, the number of puppies, and any repeat blood tests. Oral supplementation is often paired with vitamin D to support calcium absorption from the gut.

Trade-offs: Absorption from the gut is slower and less predictable than intravenous delivery, so this approach is typically used for maintenance rather than immediate correction. Over-supplementation can lead to elevated calcium in the long term, which carries its own risks, so monitoring is helpful.

Reducing or pausing lactation

Separating the dog from the puppies for a period, or weaning them onto supplemental milk, reduces the immediate demand for calcium. Some owners hand-rear the litter partially or fully, whilst others allow limited nursing under supervision. The duration of separation depends on the severity of the episode and how quickly blood calcium stabilises.

Trade-offs: Hand-rearing is time-intensive and requires commitment, particularly if the litter is large or very young. Abrupt weaning can cause engorgement of the mammary glands, which may be uncomfortable and can increase the risk of mastitis. Gradual reduction tends to be more manageable but may not be feasible if signs are advancing quickly.

Supportive care during recovery

A quiet, dimly lit environment can reduce sensory stimulation that may worsen muscle excitability or agitation. Temperature is monitored because some dogs develop hyperthermia secondary to muscle activity. Fluid therapy may be given if the dog is dehydrated or if intravenous access is already in place for calcium administration.

Trade-offs: Supportive measures do not address the calcium imbalance directly, so they are used alongside other interventions rather than as standalone treatment. The benefit is greatest in dogs with pronounced agitation or elevated body temperature, and less relevant in milder presentations.

Common misconceptions

Misconception:

"Calcium supplementation during pregnancy prevents eclampsia."

Reality:

Giving high doses of calcium before whelping can suppress the parathyroid glands, which are responsible for mobilising calcium from bone when lactation begins. This suppression may leave the dog less able to respond to the sudden demand for calcium after birth. Calcium given during lactation, once signs appear or as maintenance, is a different scenario.

Misconception:

"Eclampsia only happens in dogs with poor nutrition or inadequate diets."

Reality:

Well-fed dogs with balanced diets can still develop eclampsia if the rate of calcium loss into milk exceeds the body's capacity to mobilise reserves. Smaller breeds and those with large litters face disproportionate metabolic demands, regardless of what they were fed before or during pregnancy. Nutrition influences overall health, but it does not eliminate the risk.

Misconception:

"Once a dog has had eclampsia, she will always have it with future litters."

Reality:

Some dogs experience eclampsia only once, whilst others have recurrences with subsequent pregnancies. The risk in future litters can be influenced by litter size, monitoring during lactation, and whether supplementation is started early. Each pregnancy and lactation period is an independent metabolic challenge.

Understanding how calcium metabolism shifts during lactation can inform decisions about future breeding and the timing of weaning. If eclampsia has occurred, there may be value in discussing what signs to watch for in any future litters and what early adjustments might be workable in a home setting. The broader context of metabolic health during reproduction includes other conditions that can arise in the perinatal period, and these share some overlapping physiology.

Last reviewed: 1 July 2026 · Dr Alastair Greenway MRCVS