Fluorine-18 (18F)

Fluorine-18 (18F) is a radioactive isotope of fluorine that emits positrons. It is used in positron emission tomography.

There are several substances labeled with fluorine-18 for diagnostic purposes: fluorodeoxyglucose 18F or fluorodeoxyglucose 18F (FDG-18F), fluorodopa (18F-FD), fluorocholine 18F, thymidine 18F, florbetapir 18F, florbetaben 18F, sodium fluoride 18F.

They are administered by intravenous injection to assess cerebral and myocardial or other tissue glucose metabolism. They are used in the diagnosis of oncological, cardiac (coronary heart disease) and neurological (epilepsy and Alzheimer's disease), renal and bone diseases.

FDG is not excreted in breast milk, but radiation from 18F accumulates in the lactating breast tissue. ^{(Mitchell 2019)}

Most agencies and expert authors consider that, due to their short physical half-life, no interruption of lactation is required after PET with ¹⁸F. ^{(Mattsson 2021, Mitchell 2019, ICRP 2015 p320, Jamar 2013, Leide 2010)}

Others recommend an interruption of 1 to 4 hours ^{(ARSAC 2023, ACMUI 2019, IAEA 2018 p283)} and avoidance of contact with the infant for 12 hours to nullify the radiation accumulated in the lactating breast ^{(Jamar 2013, Leide 2010, Hendler 2010, Hicks 2001)}. During that time, milk can be expressed, not discarded, and given to the infant. ^{(Mitchell 2019, Jamar 2013, Hicks 2001)}

Nuclear medicine services can measure the radioactivity of milk so that breastfeeding can be safely resumed. ^{(Stabin 2000)}

Breastfeeding can lead to excessive uptake of 18FDG diffusely in the breast, sometimes unilaterally, depending on the breastfeeding practice, which can lead to misdiagnoses of breast cancer or lymphoma or mastitis. ^{(Ko 2013, Abhyankar 2012, Hendler 2010, Hicks 2001)}

See below the information of this related product:

• Positron Emission Tomography (Scan PET) (Safe substance and/or breastfeeding is the best option.)