Major health organizations advise against cannabis use while nursing. THC, the compound in marijuana that causes a high, passes into breast milk and can still be detected there days after use, and no safe level has been established for a nursing infant. If you use cannabis and you are breastfeeding, the standard advice is to stop or to talk with a clinician about safer feeding options.
What the major health agencies say
The guidance is consistent across the organizations that track this question.
- CDC: notes that THC has been found in breast milk and advises against marijuana use while breastfeeding.
- ACOG: recommends against marijuana use during pregnancy and lactation, citing a lack of safety data.
- LactMed (National Library of Medicine): reports limited research on cannabis in human milk and recommends avoiding it during breastfeeding, particularly with heavy or frequent use.
None of these groups describes a safe amount or a safe window between use and a feeding. The absence of evidence is treated as a reason for caution, not permission.
Why THC in breast milk is a concern
THC is fat soluble. It is stored in body fat and released back into the bloodstream over time, which is why it can appear in milk long after the last use. With repeated use, levels can build up.
A newborn's liver and brain are still developing, and THC acts on cannabinoid receptors that play a role in normal brain development. Infants also clear the compound more slowly than adults. Case reports and small studies have described sedation, feeding problems, and slower weight gain in some exposed infants, though the research is limited and mixed.
Smoke, vapor, and secondhand exposure
Inhaled cannabis adds a second risk that has nothing to do with milk. Secondhand and thirdhand smoke expose a baby to fine particles and toxins. Residue settles on skin, hair, clothing, furniture, and bedding. If anyone in the household uses cannabis, smoke outdoors and away from the baby, change clothes, and wash hands before holding or feeding an infant.
What about CBD while nursing?
CBD is not the same compound as THC, but that does not make it a safe choice during lactation.
- CBD can pass into breast milk, and there is no research establishing how it affects a nursing infant.
- The FDA has not approved CBD for use during breastfeeding and advises people who are pregnant or breastfeeding to talk with a health care provider first.
- CBD products sold online and in stores are not held to the same manufacturing standards as medicines. FDA sampling of CBD products has found items with THC, with less CBD than the label claims, and with contaminants.
- Some CBD products contain enough THC to register on a drug screen or to show up in breast milk.
If you decide to use CBD for any reason, lab-tested products with a current certificate of analysis are the only way to know what is in the bottle. That reduces the chance of an unexpected ingredient, though it does not make CBD safe during nursing.
If you are using cannabis and breastfeeding
Honest information from your clinician gets you better care than silence.
- Talk to your provider. Obstetricians, midwives, pediatricians, and lactation consultants can discuss feeding plans without judgment.
- Know that pumping and dumping does not work. THC is stored in fat and cleared slowly, so skipping or discarding milk does not shorten the exposure window the way it does for alcohol.
- Avoid smoking or vaping near the baby, and keep all products, edibles, and oils locked away.
- Ask about alternatives. Postpartum anxiety, pain, and sleep problems have other treatments, including therapy, support groups, and FDA-approved medications that are compatible with breastfeeding.
The short answer
Cannabis use while nursing is discouraged by the CDC, ACOG, and LactMed because THC reaches breast milk and the long-term effects on infants are not known. CBD carries its own unknowns and is not a substitute. Talk with a health care provider about your options before you decide.