Introduction

Selenium injection is a sterile, nonpyrogenic solution for use as an additive to solutions for total parenteral nutrition (TPN).

Each mL contains selenious acid 65.4 mcg (equivalent to elemental selenium 40 mcg/mL) and water for injection. pH may be adjusted with nitric acid to 1.8 to 2.4.

Uses for Selenious Acid

Selenium has the following uses:

Selenium injection is indicated for use as a supplement to intravenous solutions given for total parenteral nutrition (TPN). Administration of selenium in TPN solutions helps to maintain plasma selenium levels and to prevent depletion of endogenous stores and subsequent deficiency symptoms.

Selenious Acid Dosage and Administration

General

Selenium is available in the following dosage form(s) and strength(s):

Selenium injection containing selenious acid 65.4 mcg/mL (equivalent to elemental selenium 40 mcg/mL).

Dosage

Selenium injection provides 40 mcg selenium/mL. For metabolically stable adults receiving TPN, the suggested additive dosage level is 20 to 40 mcg selenium/day. For pediatric patients, the suggested additive dosage level is 3 mcg/kg/day.

In adults with selenium deficiency states resulting from long-term TPN support, selenium as selenomethionine or selenious acid, administered intravenously at 100 mcg/day for a period of 24 and 31 days, respectively, has been reported to reverse deficiency symptoms without toxicity.

Aseptic addition of selenium injection to the TPN solution under laminar flow hood is recommended. Selenium is physically compatible with the electrolytes and other trace elements usually present in amino-acid/dextrose solution used for TPN. Frequent monitoring of plasma selenium levels is suggested as a guideline for subsequent administration. The normal whole blood range for selenium is approximately 10 to 37 mcg/100 mL.

Do not directly mix ascorbic acid injection with selenium containing parenteral products in the same syringe or vial, as this admixture may cause the formation of an insoluble precipitate.

Parenteral drug products should be inspected visually for particulate matter and discoloration whenever solution and container permit.

Contraindications

Selenium injection should not be given undiluted by direct injection into a peripheral vein because of the potential for infusion phlebitis.

Warnings/Precautions

Warnings

Selenium Toxicity

Selenium injection can be toxic if given in excessive amounts. Supplementation of TPN solution with selenium should be immediately discontinued if toxicity symptoms are observed. Frequent determination of plasma selenium levels during TPN support and close medical supervision are recommended.

Hypotonicity

Selenium injection is a hypotonic solution and should be administered in admixtures only.

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 aluminum in amounts 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.

General Precautions

As selenium is eliminated in urine and feces, selenium supplements may be adjusted, reduced, or omitted in renal dysfunction and/or gastrointestinal malfunction. In patients receiving blood transfusions, contribution from such transfusions should also be considered. Frequent selenium plasma level determinations are suggested as a guideline.

In animals, selenium has been reported to enhance the action of vitamin E and decrease the toxicity of mercury, cadmium, and arsenic.

Pregnancy

Pregnancy category C. Selenium at high dose levels (15–30 mcg/egg) has been reported to have adverse embryological effects among chickens. There are, however, no adequate and well-controlled studies in pregnant women. Selenium injection should be used during pregnancy only if potential benefit justifies the potential risk to the fetus.

Presence of selenium in placenta and umbilical cord blood has been reported in humans.

Common Adverse Effects

The amount of selenium present in selenium injection is small. Symptoms of toxicity from selenium are unlikely to occur at the recommended dosage level.

General

Selenium is available in the following dosage form(s) and strength(s):

Selenium injection containing selenious acid 65.4 mcg/mL (equivalent to elemental selenium 40 mcg/mL).

Dosage

Selenium injection provides 40 mcg selenium/mL. For metabolically stable adults receiving TPN, the suggested additive dosage level is 20 to 40 mcg selenium/day. For pediatric patients, the suggested additive dosage level is 3 mcg/kg/day.

In adults with selenium deficiency states resulting from long-term TPN support, selenium as selenomethionine or selenious acid, administered intravenously at 100 mcg/day for a period of 24 and 31 days, respectively, has been reported to reverse deficiency symptoms without toxicity.

Aseptic addition of selenium injection to the TPN solution under laminar flow hood is recommended. Selenium is physically compatible with the electrolytes and other trace elements usually present in amino-acid/dextrose solution used for TPN. Frequent monitoring of plasma selenium levels is suggested as a guideline for subsequent administration. The normal whole blood range for selenium is approximately 10 to 37 mcg/100 mL.

Do not directly mix ascorbic acid injection with selenium containing parenteral products in the same syringe or vial, as this admixture may cause the formation of an insoluble precipitate.

Parenteral drug products should be inspected visually for particulate matter and discoloration whenever solution and container permit.