Manganese Chloride

INDICATIONS AND USAGE Manganese 0.1 mg/mL (Manganese Chloride Injection, USP) is indicated for use in adult patients as a supplement to intravenous solutions given for TPN. Administration helps to maintain manganese serum levels and to prevent depletion of endogenous stores and subsequent deficiency symptoms.

CLINICAL PHARMACOLOGY Manganese is an essential nutrient which serves as an activator for enzymes such as polysaccharide polymerase, liver arginase, cholinesterase and pyruvate carboxylase. Providing manganese during TPN helps prevent development of deficiency symptoms such as nausea and vomiting, weight loss, dermatitis and changes in growth and color of hair. Under conditions of minimal intake, 20 mcg manganese/day is retained. Manganese is bound to a specific transport protein, transmanganin, a beta-l-globulin. Manganese is widely distributed but concentrates in the mitochondria rich tissues such as brain, kidney, pancreas, and liver. Assays for manganese in whole blood result in concentrations ranging from 6 to 12 mcg/manganese/liter. Excretion of manganese occurs mainly through the bile, but in the event of obstruction, ancillary excretion routes include pancreatic juice, or return into the lumen of the duodenum, jejunum, or ileum. Urinary excretion of manganese is negligible.

DOSAGE AND ADMINISTRATION Manganese 0.1 mg/mL (Manganese Chloride Injection, USP) contains 0.1 mg manganese/mL and is administered intravenously only after dilution. The additive should be administered in a volume of fluid at least 100 mL. For the adult receiving TPN, the suggested additive dosage for manganese is 55 mcg/day (0.55 mL/day). Periodic monitoring of manganese plasma levels is suggested as a guideline for subsequent administration. (See WARNINGS .) Parenteral products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. (See PRECAUTIONS .)

ADVERSE REACTIONS None known.

WARNINGS Direct intramuscular or intravenous injection of Manganese 0.1 mg/mL (Manganese Chloride Injection, USP) is contraindicated as the acidic pH of the solution (pH 2.0) may cause considerable tissue irritation. Neurologic Toxicity with Manganese Manganese accumulation in the basal ganglia has been reported in adult and pediatric patients on long‑term parenteral nutrition receiving manganese at higher than recommended dosages and in association with cholestatic liver disease. Brain MRI findings and clinical symptoms have also been observed in patients who received manganese at or below the recommended dosage and with normal blood manganese concentrations. Some adult patients with brain MRI findings reportedly experienced neuropsychiatric symptoms, including changes in mood or memory, seizures and/or parkinsonian‑like tremors, dysarthria, mask-face, and halting gait. Some pediatric patients experienced dystonic movements or seizures. Regression of symptoms and MRI findings have occurred over weeks to months following discontinuation of manganese in most patients but have not always completely resolved. Monitor patients receiving parenteral nutrition solutions containing manganese for neurologic signs and symptoms and routinely measure whole blood manganese concentrations and liver tests. In case of suspected manganese toxicity or new neuropsychiatric manifestations, temporarily discontinue manganese, check manganese whole blood concentrations, and consider brain MRI evaluation. Hepatic Accumulation of Manganese Manganese is primarily eliminated in the bile and excretion is decreased in patients with cholestasis and/or cirrhosis. Hepatic accumulation of manganese has been reported in autopsies of patients receiving long-term parenteral nutrition containing manganese at dosages higher than recommended. Patients with cholestasis and/or cirrhosis receiving parenteral nutrition are at increased risk of manganese brain deposition and neurotoxicity. If a patient develops signs or symptoms of hepatobiliary disease during the use of this drug product, obtain manganese whole blood concentrations; consider discontinuing manganese supplementation in these patients until a full clinical evaluation is completed. Aluminum Toxicity This product contains aluminum that may be toxic. Aluminum may reach toxic levels with prolonged parenteral administration if kidney function is impaired. Premature neonates are particularly at risk because their kidneys are immature, and they require large amounts of calcium and phosphate solutions, which contain aluminum. Research indicates that patients with impaired kidney function, including premature neonates, who receive parenteral levels of aluminum at greater than 4 to 5 mcg/kg/day accumulate aluminum at levels associated with central nervous system and bone toxicity. Tissue loading may occur at even lower rates of administration.

CONTRAINDICATIONS None known.

OVERDOSAGE Acute manganese toxicity was reported in adult patients following infusion of manganese more than 10,000-fold the recommended dosage and after use of dialysis fluid contaminated with manganese. Signs and symptoms included skin flushing, acute pancreatitis, elevated whole blood manganese concentrations, and MRI evidence of brain accumulation of manganese. Chronic infusion and oral intake of manganese above recommended dosage have resulted in neuropsychiatric symptoms and MRI evidence of brain accumulation of manganese (see WARNINGS ).