newborn

One of the most important medicines for your newborn is the vitamin K shot administered shortly after birth, given to decrease the risk of bleeding problems in babies. Vitamin K activates clotting factors which help control bleeding. Humans get vitamin K mostly from plants, with a small amount made by bacteria in the intestines. Newborns have very low levels of vitamin K because it does not cross easily from the placenta to the baby, and do not yet have enough gut bacteria to make adequate vitamin K.  Breast milk, otherwise the best nutrition for babies, is very low in vitamin K, while formula happens to be quite high.

This vitamin K deficiency puts babies at risk of bleeding, called vitamin K deficiency bleeding (VKDB). There are 3 types- early, classic, and late. Early VKDB occurs within the first 24 hours, classic occurs in the first 2-7 days of life and late can occur any time up to age 6 months.

General signs of newborn or infantile bleeding are paleness, bruising, and bloody/tarry stools. A potentially deadly brain bleed may occur with any type of vitamin K deficiency bleeding but is most common and severe in the late type. It is the first sign of a problem in 50% of late cases, occurring with no warning. The baby may be lethargic or irritable, have a bulging soft spot, or develop seizures. Despite treatment with vitamin K by injection and surgery, the outcome is often tragic. 20% of babies who develop brain bleeds due to vitamin K deficiency die, and many survivors have brain damage. 

It is important to remember that vitamin K deficiency bleeding is rare because of preventative vitamin K 1 mg given by injection within 6 hours of birth. The vitamin K is stored in the liver and slowly released over several months. This injection decreases the risk of vitamin K deficiency bleeding to almost zero. There are no significant side effects of the shot other than the discomfort, slight swelling, and mild bruising/bleeding that may happen with any injection. Holding your baby while the injection is given can ease the discomfort. 

Some have wondered about giving vitamin K by mouth as a single dose or multiple doses over weeks, but that does not work as well. Absorption may vary, and there is no delayed release benefit. 

Making sure your baby receives their Vitamin K injection shortly after birth is vital to prevent bleeding which can occur without warning and be very dangerous. It is safe, simple, and extremely effective.