The first 3 months of life (Neonatal stage – birth to 2 weeks, infant state – 2 to 6 weeks of age and pediatric stage – 6 to 12 weeks) may be considered the pediatric period in dogs and cats.

A review of the physiologic differences affecting pharmacokinetics in neonates, the basic concepts in making drug choices for the neonatal canine and feline, the most commonly used drugs in neonates, and specific drugs commonly used and avoided in the neonate.

Although suffering from a variety of different diseases, many sick neonates present with similar clinical signs.

Neonatal pathology may involve a number of developmental malformations. A solid background in embryology and early development assists in understanding the pathogenesis of many of the conditions.