Can I take hydroxocobalamin while pregnant or breastfeeding?

8.1 Pregnancy Risk Summary Available data from cases reported in the published literature and postmarketing surveillance with CYANOKIT use in pregnant women are insufficient to identify a drug-associated risk for major birth defects, miscarriage, or adverse maternal and fetal outcomes. There are risks to the pregnant woman and fetus associated with untreated cyanide poisoning (see Clinical Considerations) . In animal studies, hydroxocobalamin administered to pregnant rats and rabbits during the period of organogenesis caused skeletal and soft tissue abnormalities, including alterations in the central nervous system, at exposures similar to human exposures at the therapeutic dose (see Data) . The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively.

Prescribing label, section “8.1 Pregnancy” (opening excerpt): Cyanokit (intravenous), BTG INTERNATIONAL INC. Read the full section on DailyMed. Quoted verbatim; US labels are written for US prescribers and patients.

This quote is from the intravenous formulation label.

Vitamin B12 is a normal component of human milk.[1] The recommended daily intake in lactating women is 2.8 mcg and for infants aged 6 months or less is 0.4 mcg.[2] Some authorities recommend 5.5 mcg per day during lactation.[3] Supplementation may be necessary to achieve these recommended daily intakes or to correct a known deficiency. Low doses (1 to 10 mcg) of vitamin B12 found in B complex or prenatal vitamins increase milk levels only slightly. Higher daily doses of 50 to 250 mcg are needed in cases of maternal deficiency. The breastfed infant is not exposed to excessive vitamin B12 in such cases, and their vitamin B12 status should improve if it was previously inadequate.

Poor health outcomes in infants with vitamin B12 deficiency include anemia, abnormal skin and hair development, convulsions, weak muscle tone, failure to thrive, mental developmental delay, and potentially abnormal movements.[4-8] Well-recognized at risk groups are exclusively breastfed infants of mothers with B12 deficiency due to minimal or no dietary intake of animal products[9-21] or pernicious anemia caused by a maternal malabsorption of B12.[18,22] Infant vitamin B12 status can be improved through maternal B12 supplementation during pregnancy and lactation.[23-26] Deficient mothers who miss the opportunity to supplement during pregnancy should still be encouraged to supplement during early lactation since infant vitamin B12 status correlates with milk vitamin B12 levels in breastfed infants up to 6 months of age.[27-30] Although there are cases reported of exclusively breastfed infants with vitamin B12 deficiency having biochemical and clinical improvement through adequate maternal supplementation alone,[9] direct supplementation of the infant is recommended when such treatments are available.[31-33]

“Summary of Use during Lactation”, LactMed record “Vitamin B 12” (LM1437), quoted verbatim. Everything LactMed reports about Vitamin B 12 while breastfeeding.

8.2 Lactation Risk Summary Breastfeeding is not recommended during treatment with CYANOKIT. There are no data to determine when breastfeeding may be safely restarted following administration of CYANOKIT. Hydroxocobalamin and Vitamin B12 (which is formed when hydroxocobalamin combines with cyanide) are present in human milk. There are no data on the effects of hydroxocobalamin on the breastfed infant or the effects on milk production.

Prescribing label, section “8.2 Lactation”: Cyanokit (intravenous), BTG INTERNATIONAL INC. Label on DailyMed. Quoted verbatim; US labels are written for US prescribers and patients.

This quote is from the intravenous formulation label.