Cyanocobalamin

NASCOBAL is indicated for: Vitamin B 12 maintenance therapy in adult patients with pernicious anemia who are in remission following intramuscular vitamin B 12 therapy and who have no nervous system involvement Treatment of adult patients with dietary, drug-induced, or malabsorption-related vitamin B 12 deficiency not due to pernicious anemia Prevention of vitamin B 12 deficiency in adult patients with vitamin B 12 requirements in excess of normal Limitations of Use NASCOBAL should not be used for the vitamin B 12 absorption test (Schilling test). In patients with correctible or temporary causes of vitamin B 12 deficiency, the benefit of continued long-term use of NASCOBAL following adequate correction of vitamin B 12 deficiency and underlying disease has not been established.

Vitamin B 12 can be converted to coenzyme B 12 in tissues, and as such is essential for conversion of methylmalonate to succinate and synthesis of methionine from homocysteine, a reaction which also requires folate. In the absence of coenzyme B 12, tetrahydrofolate cannot be regenerated from its inactive storage form, 5-methyltetrahydrofolate, and a functional folate deficiency occurs. Vitamin B 12 also may be involved in maintaining sulfhydryl (SH) groups in the reduced form required by many SH-activated enzyme systems. Through these reactions, vitamin B 12 is associated with fat and carbohydrate metabolism and protein synthesis.

Prior to treatment, obtain hematocrit, reticulocyte count, vitamin B 12, folate, and iron levels. The recommended initial dose is one spray (500 mcg) in one nostril once weekly. Administer at least one hour before or one hour after ingestion of hot foods or liquids. Monitor serum B12 levels periodically.Obtain a serum B12 level and peripheral blood count one month after treatment initiation, then subsequently at intervals of 3 to 6 months. If serum levels of B12 decline after one month of treatment, consider increasing the dose. Assess serum B12 level one month after each dose adjustment.If serum B12 levels are persistently low, consider alternative therapy (e.g., intramuscular or subcutaneous vitamin B12 therapy). See Full Prescibing Information to see what other therapies should be administered with NASCOBAL.

NASCOBAL is contraindicated in patients with hypersensitivity to cobalt and/or vitamin B 12 or any of its excipients. Anaphylactic shock and death have been reported after parenteral vitamin B12 administration in sensitive patients. • Hypersensitivity to cobalt, vitamin B 12 or any excipients

• 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. NASCOBAL is not recommended for use in these patients. • Anaphylactic Reactions: Anaphylactic shock and death have been reported after parenteral vitamin B 12 administration. If patients are to start NASCOBAL before having tolerated cyanocobalamin parenterally, consider administering an intradermal test dose of parenteral vitamin B 12 to patients suspected of cyanocobalamin hypersensitivity. • 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.

The following serious adverse reactions are described elsewhere in the labeling: Severe Optic Atrophy in Patients with Leber’s Disease. Anaphylactic Reactions. Hypokalemia and Thrombocytosis Due to Intense Treatment of Megaloblastic Anemia. The most common adverse reactions (≥ 4%) were infection, headache, glossitis, paresthesia, asthenia, nausea and rhinitis

Chloramphenicol may decrease the efficacy of NASCOBAL when used for treatment of anemia. If NASCOBAL is used for the treatment of anemia concomitantly with chloramphenicol, monitor for reduced efficacy and if needed, consider an alternative therapy

Store upright at controlled room temperature 15°C to 30°C (59°F to 86°F). Protect from freezing.