April 30, 2017
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Nasal spray
(cyanocobalamin, USP)
500 mcg/spray
2.3 mL (8 sprays)


Cyanocobalamin is a synthetic form of vitamin B12 with equivalent vitamin B12 activity. The chemical name is 5,6-dimethyl-benzimidazolyl cyanocobamide. The cobalt content is 4.35%. The molecular formula is C63H88CoN14O14P, which corresponds to a molecular weight of 1355.38 and the following structural formula:

Nascobal (Cyanocobalamin, USP) Structural Formula Illustration

Cyanocobalamin occurs as dark red crystals or orthorhombic needles or crystalline red powder. It is very hygroscopic in the anhydrous form, and sparingly to moderately soluble in water (1:80). Its pharmacologic activity is destroyed by heavy metals (iron) and strong oxidizing or reducing agents (vitamin C), but not by autoclaving for short periods of time (15-20 minutes) at 121°C. The vitamin B12 coenzymes are very unstable in light.

Nascobal® Nasal Spray is a solution of Cyanocobalamin, USP (vitamin B12) for administration as a spray to the nasal mucosa. Each bottle of Nascobal (cyanocobalamin) Nasal Spray contains 2.3 mL of a 500 mcg / 0.1 mL solution of cyanocobalamin with sodium citrate, citric acid, glycerin and benzalkonium chloride in purified water. The spray solution has a pH between 4.5 and 5.5. The spray pump unit must be fully primed (see DOSAGE AND ADMINISTRATION) prior to initial use. After initial priming, each spray delivers an average of 500 mcg of cyanocobalamin and the 2.3 mL of spray solution contained in the bottle will deliver 8 doses of Nascobal (cyanocobalamin) Nasal Spray. The unit must be re-primed before each dose. (see DOSAGE AND ADMINISTRATION).

What are the possible side effects of nasal cyanocobalamin (CaloMist, Nascobal)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have a serious side effect such as:

  • chest pain;
  • feeling short of breath, even with mild exertion;
  • swelling, rapid weight gain; or
  • unusual warmth, redness, or pain in an arm or leg.

Less serious side effects may include:

  • headache, dizziness, weakness;
  • nausea, upset stomach, diarrhea;
  • numbness or...

Read All Potential Side Effects and See Pictures of Nascobal »

What are the precautions when taking cyanocobalamin (Nascobal)?

Before using cyanocobalamin, tell your doctor or pharmacist if you are allergic to it; or to cobalt; or if you have any other allergies. Your doctor may recommend that you receive a smaller test dose before starting your regular dose. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: low potassium blood levels (hypokalemia), gout, a certain blood disorder (polycythemia vera), a certain eye disease (Leber's disease), other vitamin/mineral deficiencies (especially folic acid and iron).

Tell your doctor if you develop a stuffy or runny nose (e.g., due to a common cold or allergies) while...

Read All Potential Precautions of Nascobal »

Last reviewed on RxList: 12/12/2016
This monograph has been modified to include the generic and brand name in many instances.

Nascobal - User Reviews

Nascobal User Reviews

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