Medically reviewed on February 13, 2018.
What is hydroxocobalamin?
Hydroxocobalamin is a form of vitamin B-12. It is used as an antidote to cyanide poisoning. Hydroxocobalamin works by helping cells in the body convert cyanide to a form that can be removed from the body through urination.
Hydroxocobalamin is used in an emergency to treat cyanide poisoning. This type of poisoning can occur if you are exposed to smoke from a house or industrial fire, if you swallow or breathe in cyanide, or if you get cyanide on your skin.
Hydroxocobalamin may also be used for purposes not listed in this medication guide.
In an emergency situation it may not be possible to tell your caregivers about your health conditions. Make sure any doctor caring for you afterward knows you have received this medicine.
Before taking this medicine
If possible before you receive hydroxocobalamin, tell your caregivers if you have:
congestive heart failure;
kidney disease (or if you are on dialysis); or
FDA pregnancy category C. Tell your doctor if you are pregnant. It is not known whether hydroxocobalamin will harm an unborn baby. However, the benefits of treating cyanide poisoning may outweigh any risks posed by hydroxocobalamin, for both you and your baby.
It is not known whether hydroxocobalamin passes into breast milk or if it could harm a nursing baby. You should not breast-feed after you have been treated with hydroxocobalamin.
In an emergency situation, it may not be possible before you are treated with hydroxocobalamin to tell your caregivers if you are pregnant or breast feeding. Make sure any doctor caring for your pregnancy or your baby knows you have received this medication.
How should I take hydroxocobalamin?
Hydroxocobalamin is injected into a vein through an IV. You will receive this injection in a clinic or hospital setting. Hydroxocobalamin must be given slowly, and the IV infusion can take at least 15 minutes to complete.
Hydroxocobalamin is usually given only once. However, you may receive a second dose if needed.
Your breathing, blood pressure, oxygen levels, heart function, and other vital signs will be watched closely while you are receiving hydroxocobalamin.
This medication can cause unusual results with certain medical tests. Tell any doctor who treats you that you have recently received a hydroxocobalamin injection.
What happens if I miss a dose?
Since hydroxocobalamin is given by a healthcare professional in an emergency setting, you are not likely to miss a dose.
What happens if I overdose?
Since this medication is given by a healthcare professional in a medical setting, an overdose is unlikely to occur.
What should I avoid while taking hydroxocobalamin?
If your skin turns red after receiving this medication, avoid exposure to sunlight or tanning beds. Hydroxocobalamin can make you sunburn more easily while your skin is still red. Wear protective clothing and use sunscreen (SPF 30 or higher) until your skin color returns to normal.
Hydroxocobalamin side effects
Get emergency medical help if you have any of these signs of an allergic reaction: hives; chest tightness, difficulty breathing; swelling of your face, lips, tongue, or throat.
You may develop an acne-like skin rash within 1 to 4 weeks after you are treated with hydroxocobalamin. This rash should go away without treatment. Call your doctor if you have a rash that lasts longer than 4 weeks.
Call your doctor at once if you have a serious side effect such as:
bright red blood in your stools;
chest pain, fast or uneven heart rate;
severe shortness of breath, wheezing, gasping for breath, cough with foamy mucus;
swelling in your feet or ankles;
a light-headed feeling, like you might pass out; or
Common side effects may include:
acne, skin rash or redness;
red coloring of your urine (may last 2 to 5 weeks); or
pain, swelling, or irritation of your skin where the injection was given.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
See also: Side effects (in more detail)
Hydroxocobalamin dosing information
Usual Adult Dose for Schilling Test:
1000 mcg IM
Usual Adult Dose for Vitamin B12 Deficiency:
Initial dose: 30 mcg IM once daily for 5 to 10 days, or 100 mcg IM once daily for one week, followed by 100 mcg IM every other day for 2 weeks.
Maintenance dose: 100 to 200 mcg IM once a month
Initial dose: 1000 mcg IM once with folic acid 15 mg, followed by 100 mcg once daily with folic acid 5 mg daily for 1 week
Maintenance dose: 100 to 200 mcg IM once a month
Usual Adult Dose for Cyanide Poisoning:
5 g, intravenously, as a single infusion over 15 minutes. May repeat a second 5 g dose, depending on the severity of poisoning and clinical response, for a maximum cumulative dose of 10 g.
Usual Pediatric Dose for Schilling Test:
1000 mcg IM
Usual Pediatric Dose for Transcobalamin II Deficiency:
Neonates: 1000 mcg IM twice a week
Usual Pediatric Dose for Vitamin B12 Deficiency:
Initial dose: 100 mcg IM daily for 10 to 15 days for a total dose of 1 to 5 mg, then maintenance of 60 mcg/month;
or 30 to 50 mcg/day for at least two weeks for a total dose of 1 to 5 mg, then maintenance of 100 mcg/month.
What other drugs will affect hydroxocobalamin?
Other drugs may interact with hydroxocobalamin, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.
Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
Copyright 1996-2018 Cerner Multum, Inc. Version: 3.03.
More about hydroxocobalamin
- Hydroxocobalamin Side Effects
- During Pregnancy
- Dosage Information
- Drug Interactions
- Support Group
- En Español
- 2 Reviews – Add your own review/rating
- Drug class: vitamins
- Hydroxocobalamin Injection
- Hydroxocobalamin Injection (Cyanide Poisoning)
- Hydroxocobalamin Intravenous (Advanced Reading)
Other brands: Cyanokit