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May 2021

THC Stays in Breastmilk Much Longer Than You Think

THC stays in breastmilk longer than alcohol – we’ve known this for a while. But we didn’t realize quite how long until now. Make sure your pregnant and breastfeeding patients understand these new findings.

It was previously estimated that THC remained in breastmilk for up to six days after using cannabis. This was a huge underestimate – likely because most research relied on self-reported use. New observational research shows that it actually stays in breastmilk for more than 6 weeks. In fact, THC levels in breastmilk may actually increase during the first two weeks after stopping use, then taper off. But they remain detectable through 6 weeks.

Talk to your pregnant and breastfeeding patients about their cannabis use. Make sure they understand that exposing infants to THC can lead to long-term consequences, including delayed development. The “pump and dump” method won’t work – patients must refrain from using cannabis until they are no longer breastfeeding. And reiterate that exposure during pregnancy poses even greater risks, including premature birth, stillbirth, increased risk for developmental disorders such as autism, and increased risk for psychological issues during adolescence.

Catching cannabis use early is crucial. Help patients find a safe alternative therapy if they are using cannabis for specific symptoms. And tell patients with dependence or addiction that help is available – non-judgmental and confidential treatment groups are established in many states.

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