CYANOCOBALAMIN Drug Interactions: What You Need to Know

INTERACTIONS Chloramphenicol may decrease the efficacy of Cyanocobalamin Nasal Spray when used for treatment of anemia.

If Cyanocobalamin Nasal

Spray is used for the treatment of anemia concomitantly with chloramphenicol, monitor for reduced efficacy and if needed, consider an alternative therapy.

CONTRAINDICATIONS Sensitivity to cobalt and/or vitamin B 12 is a contraindication. WARNINGS: Patients with early Leber's disease (hereditary optic nerve atrophy) who were treated with cyanocobalamin suffered severe and swift optic atrophy. Hypokalemia and sudden death may occur in severe megaloblastic anemia which is treated intensely. Anaphylactic shock and death have been reported after parenteral vitamin B 12 administration. An intradermal test dose is recommended before Cyanocobalamin Injection, USP is administered to patients suspected of being sensitive to this drug. This product contains Benzyl Alcohol.

Benzyl

Alcohol has been reported to be associated with a fatal "Gasping Syndrome" in premature infants. 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.

AND PRECAUTIONS

• Severe Optic Atrophy in Patients with Leber’s Disease: Patients with early Leber’s disease who were treated with vitamin B 12 suffered severe and swift optic atrophy.

Cyanocobalamin Nasal

Spray is not recommended for use in these patients. ( 5.1 )

• Anaphylactic Reactions: Anaphylactic shock and death have been reported after parenteral vitamin B 12 administration. If patients are to start Cyanocobalamin Nasal Spray before having tolerated cyanocobalamin parenterally, consider administering an intradermal test dose of parenteral vitamin B 12 to patients suspected of cyanocobalamin hypersensitivity. ( 2.1 , 5.2 )
• Masking of Folate Deficiency with Vitamin B 12 Use: Doses of vitamin B 12 exceeding 10 mcg daily may produce hematologic response in patients with folate deficient megaloblastic anemia and may therefore mask a previously unrecognized folate deficiency. Assess both vitamin B 12 and folate levels prior to initiating therapy with Cyanocobalamin Nasal Spray or with folic acid. ( 5.3 )
• Hypokalemia and Thrombocytosis Due to Intense Treatment of Megaloblastic Anemia: Hypokalemia and sudden death may occur in severe megaloblastic anemia that is treated intensely with vitamin B 12 . Monitor serum potassium levels and platelet count during therapy. ( 5.4 )
• Unmasking of Polycythemia Vera: Vitamin B 12 deficiency may suppress the signs of polycythemia vera. Treatment with Cyanocobalamin Nasal Spray may unmask this condition. Patients exhibiting clinical or hematologic response consistent with polycythemia vera should be referred for further evaluation. ( 5.5 )

5.1 Severe Optic Atrophy in Patients with Leber’s Disease Patients with early Leber’s disease (hereditary optic nerve atrophy) who were treated with vitamin B 12 suffered severe and swift optic atrophy. Cyanocobalamin products, including Cyanocobalamin Nasal Spray, is not recommended for use in patients with Leber’s optic atrophy. For patients with Leber’s disease requiring vitamin B 12 , consider alternative therapy (e.g., hydroxocobalamin) for B 12 supplementation.

5.2 Anaphylactic Reactions Anaphylactic shock and death have been reported after parenteral vitamin B 12 administration. If patients are to start Cyanocobalamin Nasal Spray before having tolerated cyanocobalamin parenterally, consider administering an intradermal test dose of parenteral vitamin B 12 to patients suspected of cyanocobalamin hypersensitivity <span class="opacity-50 text-xs">[see Dosage and Administration (2.1) ]</span> .

5.3 Masking of Folate Deficiency with Vitamin B 12 Use Doses of vitamin B 12 exceeding 10 mcg daily may produce hematologic response in patients with folate deficient megaloblastic anemia and may therefore mask a previously unrecognized folate deficiency. Vitamin B 12 is not a substitute for folic acid <span class="opacity-50 text-xs">[see Dosage and Administration (2.4) ]</span> . Assess both vitamin B 12 and folate levels prior to initiating therapy with vitamin B 12 , including Cyanocobalamin Nasal Spray, or with folic acid <span class="opacity-50 text-xs">[see Dosage and Administration (2.1) ]</span> .

5.4 Hypokalemia and Thrombocytosis Due to Intense Treatment of Megaloblastic Anemia Hypokalemia and sudden death may occur in severe megaloblastic anemia that is treated intensely with vitamin B 12 . Hypokalemia and thrombocytosis can occur upon conversion of severe megaloblastic anemia to normal erythropoiesis with vitamin B 12 therapy. Therefore, serum potassium levels and platelet count should be monitored carefully during therapy <span class="opacity-50 text-xs">[see Dosage and Administration (2.3) ]</span> .

5.5 Unmasking of Polycythemia Vera Vitamin B 12 deficiency may suppress the signs of polycythemia vera. Treatment with vitamin B 12 may unmask this condition. Patients exhibiting clinical or hematologic response consistent with polycythemia vera should be referred for further evaluation.