Eclampsia (Milk Fever)

What is it?

Eclampsia (hypocalcemia, puerperal tetany, lactation tetany) is a dangerous drop in blood calcium linked to the demands of milk production. In cats it most often occurs in the weeks after birth, while the kittens are about one to five weeks old, and can occasionally occur before birth. Causes may include calcium loss to the kittens and milk, an unbalanced diet, calcium supplements during pregnancy, or a parathyroid problem. Mothers nursing large litters or that are very attentive are more likely to be affected.

What signs should I watch for?

Early signs are subtle and can include lethargy, poor appetite, restlessness, panting, trembling, and incoordination. It can progress to rigid, stiff-legged muscle spasms, convulsions, or coma. She may have pale gums, a low body temperature, trouble breathing or fast breathing, and a slow heart rate. If you suspect eclampsia, stop the kittens from nursing and contact your veterinarian immediately.

How is it diagnosed and treated?

Treatment includes intravenous fluids and calcium, given slowly while the heart is monitored, and sometimes anti-seizure medication. Follow-up often includes oral calcium supplements, and kittens are weaned or given supplementary feeding.

Can it be prevented, and what's the outlook?

• With prompt treatment, recovery is usually rapid and complete.
• Feed a high-quality diet made for pregnant and nursing mothers, and avoid calcium supplements or dairy during pregnancy unless your veterinarian advises them.
• Eclampsia often recurs with later litters, so an affected cat should raise only a small litter next time, and this should factor into decisions about breeding her again.