CBD is not considered safe for babies. No regulatory agency has approved CBD for infants, and the biological evidence points to real risks: an infant’s brain and liver are still developing in ways that make them uniquely vulnerable to cannabinoids. The FDA explicitly advises against CBD use during breastfeeding, and the only prescription CBD product on the market is not approved for children under two.
Why Infant Biology Makes CBD Risky
The body’s internal cannabinoid system, called the endocannabinoid system, is active from the earliest stages of embryonic development. In the fetal brain, cannabinoid receptors help guide how nerve cells specialize, how brain wiring forms, and how connections between neurons are built. After birth, this same system appears to play a role in basic survival behaviors. In animal studies, activating cannabinoid receptors helped newborn mice initiate milk suckling, likely by enabling the nerve signals that control tongue muscles.
Because this system is so deeply involved in brain wiring and early development, introducing an outside cannabinoid like CBD can interfere with those tightly regulated processes. Animal research has shown that manipulating the cannabinoid system during the period around birth alters neurotransmitter function and behavior in offspring. In a 2025 rat study, prenatal CBD exposure at higher doses led to lower birth weight, reduced weight gain before weaning, and decreased performance on a homing behavior test (a measure of early cognitive and sensory development). Some of these differences resolved by three weeks of age, but the findings underscore that the developing brain responds to CBD differently than an adult brain does.
An Infant’s Liver Can’t Process CBD Like an Adult’s
CBD is broken down primarily by liver enzymes, and a baby’s liver enzyme system is dramatically immature at birth. One key enzyme involved in CBD metabolism operates at roughly 30% of adult capacity at birth, reaching adult-comparable levels only around five months of age. Another starts at just 15% of adult activity and increases slowly over the first several months. A separate group of enzymes responsible for a later stage of CBD processing begins at less than 1% of adult levels and can take anywhere from three months to three years or more to mature.
This immaturity means a baby’s body clears CBD far more slowly and unpredictably than an adult’s. The practical concern is accumulation: CBD and its breakdown products could linger in an infant’s system at higher concentrations and for longer periods than anyone can reliably predict, since no dosing studies have been conducted in this age group.
Known Side Effects, Even in Older Children
The closest thing to rigorous pediatric CBD safety data comes from Epidiolex, the only FDA-approved CBD medication. It is approved for children aged two and older with severe seizure disorders, and even under medical supervision, the side effect profile is significant. In clinical trials, about one in three children taking the standard dose experienced drowsiness or sedation. One in five had decreased appetite. One in five developed diarrhea. And 16% showed elevated liver enzymes, a sign of liver stress, compared to just 3% on placebo.
These are controlled, pharmaceutical-grade doses in children who are at least two years old and being monitored with regular blood tests. For babies under two, safety and effectiveness have simply not been established. Outside of that clinical context, CBD has also been linked to seizures in toddlers, and poison control centers have reported a rise in CBD poisoning cases involving children who consumed edibles or adult products. Warning signs of CBD poisoning in a child include unexplained vomiting, fever, or unusual drowsiness.
CBD in Breast Milk
If you use CBD while breastfeeding, some amount will reach your baby through your milk. A 2023 modeling study measured CBD concentrations in breast milk and estimated the doses infants would receive. The amounts were small but varied widely depending on how the mother consumed CBD. Mothers who used CBD oil or smoked it from a pipe produced milk with average concentrations around 9.7 ng/mL, roughly ten times higher than mothers who used edibles or smoked joints (about 0.94 ng/mL). The estimated dose reaching the infant ranged from about 0.1 ng per kilogram of body weight on the low end to 2.2 ng/kg on the high end.
While these are tiny quantities, they land in a body with immature liver enzymes that may not clear them efficiently. The longer the time between a mother’s dose and breastfeeding, the lower the concentration in milk tends to be, but there is no established “safe” waiting period. The FDA notes that THC can remain in breast milk for up to six days after use, and given CBD’s similar fat-soluble properties, it likely persists as well.
Unregulated Products Add Another Layer of Risk
Consumer CBD products are not held to pharmaceutical standards, and contamination is common. A study analyzing 80 commercially available CBD products found THC in the majority of them, with concentrations ranging from negligible to 2.07 mg/mL. For context, the FDA-approved pharmaceutical version contained just 0.022 mg/mL of THC. Among 21 products specifically labeled “THC-Free,” five still contained detectable THC, with one reaching 0.656 mg/mL.
THC is the compound in cannabis that produces a high, and it poses its own developmental risks to infants, including potential effects on brain development, hyperactivity, and cognitive function. Beyond THC, unregulated CBD products have been found to contain synthetic cannabinoids, residual solvents, heavy metals, and in some cases no measurable CBD at all. Giving a baby a product with this level of quality uncertainty compounds the biological risks considerably.
What the FDA Says
The FDA’s position is unambiguous: it strongly advises against using CBD, THC, or marijuana in any form while pregnant or breastfeeding. The agency expects that some CBD transfers to babies through breast milk and has not approved any CBD product for infants. The sole approved pediatric CBD medication carries a minimum age of two years, and even that comes with mandatory liver monitoring and a substantial side effect profile. No over-the-counter or supplement-grade CBD product has been evaluated or approved for use in any child, let alone a baby.