Is Lithium safe while breastfeeding?

Effects on the breastfed infant

In older reports, at least 24 infants have been reported to have been breastfed during maternal lithium therapy without any signs of toxicity or developmental problems. All were breastfed from birth and some continued to nurse for up to 6 months of maternal lithium therapy.[ 17 , 20 - 22 , 26 , 27 , 29 ] A 5-day-old infant developed cyanosis, lethargy, ECG T-wave inversion probably caused by lithium in breastmilk.[ 24 ] The mother had been receiving the long-acting diuretic chlorthalidone prior to delivery which probably decreased the infant's lithium elimination and increased the neonate's lithium serum levels. Another case of probable infant lithium intoxication appeared only after the infant had a cold which may have led to dehydration and decreased lithium excretion.[ 28 , 35 ] Two other infants had slight increases in thyrotropin (TSH) levels at 8 and 4 weeks of age, respectively, after lithium exposure that began during pregnancy. Elevated TSH continued until maternal lithium was stopped in one,[ 17 ] and normalized by 2 months postpartum in the other, despite continued exclusive breastfeeding.[ 29 ] Three mothers took lithium carbonate during pregnancy and breastfeeding. The first infant was born to a mother who also took bupropion 300 mg and levothyroxine 50 to 75 mcg daily. She breastfed beyond 1 year of age. Her infant did not regain birth weight by 15 days of age, was somewhat hypotonic at 2 months of age, and was treated for gross and fine motor delay for the first year of life. The mother had a second infant on the same drug regimen. She exclusively breastfed her infant who developed normally without hypotonia. A second mother was taking a lithium dosage of 900 mg daily. Her infant gained weight slowly, but weight gain increased with breastfeeding support, and she exclusively breastfed her infant for 4 months. A third mother was taking 1350 mg of lithium daily as well as escitalopram 10 mg, levothyroxine 25 mcg and heparin (dosage not stated) daily duri

Effects on milk supply

Lithium increases serum prolactin.[ 36 - 38 ] Galactorrhea was reported in a woman taking lithium carbonate for 50 days. Lactation ceased with lithium discontinuation.[ 38 ] The prolactin level in a mother with established lactation may not affect her ability to breastfeed.

Levels in milk

Maternal Levels. Most older reports of lithium levels in breastmilk did not characterize breastmilk lithium excretion in a rigorous manner. Random milk levels have been reported to range from 0.12 to 0.7 mEq/L and appear to be rather consistent at about 40 to 45% of the simultaneous maternal serum level.[ 19 - 22 ] The milk concentration of lithium in one woman was found to be inversely proportional to milk volume. The milk to plasma ratio was found to be directly proportional to serum lithium; the ratio was about 1 with low serum lithium and 1.5 with higher serum lithium levels, indicating disproportionately higher lithium excretion into milk with higher serum levels.[ 23 ] From data published up to 1990 concerning 6 infants, it is estimated that a fully breastfed infant would receive about 26% (range 11 to 42%) of the maternal weight-adjusted dosage of lithium.[ 20 - 25 ] However, many of these case reports were of poor quality. A more recent case series of 11 mothers that used better techniques found the relative infant dosage to be 12.2% (range 0 to 30%) of the maternal weight-adjusted dosage.[ 26 ] The reason for the difference between the older and more recent data is not apparent. A case series reported 10 mothers taking lithium carbonate in an average daily dosage of 850 mg (range 600 to 1200 mg daily) for bipolar disorder. Lithium milk levels in 26 milk samples taken between 8.1 and 27.5 weeks postpartum averaged 0.35 mEq/L (range 0.19 to 0.48 mEq/L). No difference was found between concentrations in fore- and hindmilk samples.[ 17 ] One woman who was taking 1200 mg of lithium carbonate daily (dosage schedule and product not reported) had a milk lithium concentration of 0.41 mmol/L at 20 hours after her previous dose. This was about the same as her simultaneous blood concentration.[ 27 ] Infant Levels. The serum lithium levels in the breastfed infants of mothers taking lithium have ranged from 10 to 50% of simultaneous maternal serum lithium levels.[ 20 , 2

Alternatives LactMed lists

• Olanzapine
• Quetiapine
• Risperidone
• Valproic Acid