TY  - BOOK
AU  - Miodovnik, Menachem
AU  - Umans, Jason G
TI  - Interpreting tacrolimus concentrations during  pregnancy and postpartum. [Review]
SN  - 0041-1337
PY  - 2013///
KW  - *Drug Monitoring
KW  - *Immunosuppressive Agents/bl [Blood]
KW  - *Organ Transplantation
KW  - *Postpartum Period/bl [Blood]
KW  - *Pregnancy Complications/pc [Prevention & Control]
KW  - *Tacrolimus/bl [Blood]
KW  - Breast Feeding
KW  - Female
KW  - Fetal Blood/me [Metabolism]
KW  - Fetus/de [Drug Effects]
KW  - Humans
KW  - Immunosuppressive Agents/ae [Adverse Effects]
KW  - Immunosuppressive Agents/pk [Pharmacokinetics]
KW  - Maternal Exposure
KW  - Maternal-Fetal Exchange
KW  - Milk, Human/me [Metabolism]
KW  - Placental Circulation
KW  - Pregnancy Complications/bl [Blood]
KW  - Pregnancy Complications/im [Immunology]
KW  - Pregnancy
KW  - Protein Binding
KW  - Risk Assessment
KW  - Risk Factors
KW  - Tacrolimus/ae [Adverse Effects]
KW  - Tacrolimus/pk [Pharmacokinetics]
KW  - MedStar Health Research Institute
KW  - Journal Article
KW  - Research Support, N.I.H., Extramural
KW  - Review
N1  - Available online from MWHC library: 1996 -  present, Available in print through MWHC library: 1999 -  2006
N2  - Pregnancy after solid organ transplantation,  although considered high risk for maternal, fetal, and  neonatal complications, has been quite successful.  Tacrolimus pharmacokinetic changes during pregnancy make  interpretation of whole blood trough concentrations  particularly challenging. There are multiple factors that  can increase the fraction of unbound tacrolimus, including  but not limited to low albumin concentration and low red  blood cell count. The clinical titration of dosage to  maintain whole blood tacrolimus trough concentrations in the  usual therapeutic range can lead to elevated unbound  concentrations and possibly toxicity in pregnant women with  anemia and hypoalbuminemia. Measurement of plasma or unbound  tacrolimus concentrations for pregnant women might better  reflect the active form of the drug, although these are  technically challenging and often unavailable in usual  clinical practice. Tacrolimus crosses the placenta with in  utero exposure being approximately 71% of maternal blood  concentrations. The lower fetal blood concentrations are  likely due to active efflux transport of tacrolimus from the  fetus toward the mother by placental P-glycoprotein. To  date, tacrolimus has not been linked to congenital  malformations but can cause reversible nephrotoxicity and  hyperkalemia in the newborn. In contrast, very small amounts  of tacrolimus are excreted in the breast milk and are  unlikely to elicit adverse effects in the nursing infant
UR  - http://dx.doi.org/10.1097/TP.0b013e318278d367
ER  -