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Brand Name(s) : Cobalin-H, Neo-Cytamen
Side Effects


Hydroxocobalamin should be used with caution in: people with a history of deficiency of folic acid and people with heart problems.

It should not be used in: people allergic to hydroxocobalamin or any other ingredient in the medicine.

Also see list of precautions and interactions.


Protect from light and store below 25°C.


What is it used for?

  • Hydroxocobalamin is used to treat conditions involving a deficiency (low levels) of vitamin B12.
  • It is one of the group of chemicals called cobalamins, which are sometimes known as forms of vitamin B12.
  • It is used to treat low levels of vitamin B12 as hydroxocobalamin is a form of vitamin B12.
  • In general this drug is used to treat low levels of vitamin B12, either because of a low level of vitamin B12 in the diet or poor absorption of this vitamin. Treatment with hydroxocobalamin may be needed after stomach or intestine (gut) surgery, or certain diseases of the intestines, as enough vitamin B12 may not be absorbed. Lack of vitamin B12 in the body causes a disease called pernicious anaemia (reduction in the number of red blood cells) which can be treated with hydroxocobalamin injections.
  • Benefits of being on this drug can include relief of the symptoms and effects of vitamin B12 deficiency.

Listed below are the typical uses of hydroxocobalamin.

  • Treatment of pernicious anaemia
  • Prevention and treatment of other anaemias due to vitamin B12 deficiency
  • Treatment of tobaccoamblyopia (poor sight caused by toxins such as tobacco)
  • Treatment of Leber’s atrophy (degeneration of the optic nerve resulting in loss of central vision).

On occasion your doctor may prescribe this medicine to treat a condition not on the above list. Such conditions are listed below.

  • Use as an antidote to cyanide poisoning.


How often do I take it?

  • Take this medication by intramuscular injection, given by a doctor or other healthcare provider.
  • Use this medication regularly in order to get the most benefit from it.
  • Remember to use it at the same time each day - unless specifically told not to by your doctor.
  • It may take some time before the full benefit of this drug takes effect.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • None known. Consult your doctor or pharmacist for more details.

When can I stop?

  • It is important to continue taking this medication even if you feel well, unless your doctor tells you to stop.


If any of these persist or you consider them severe then inform your doctor or pharmacist.

Tell your doctor immediately if you develop any of the following symptoms: any heartbeat irregularities.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.


Before taking hydroxocobalamin, tell your doctor or pharmacist if you are allergic to it; or to other vitamin; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist in case of: allergy to hydroxocobalamin or to other vitamins

Before using this medication tell your doctor or pharmacist your medical history, especially any of the following: a history of deficiency of folic acid or heart problems.

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • It is not known whether drinking alcohol affects this drug's action.

The elderly: hydroxocobalamin can be used in the elderly.

Pregnancy and breastfeeding - please ensure you read the detailed information below


Hydroxocobalamin is not suitable to use in megaloblastic anaemia of pregnancy. Ask your doctor or pharmacist if you have any doubts or questions about this.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Hydroxocobalamin is suitable to take if you are breastfeeding.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.

This drug should not be used with the following medications because very serious, possibly fatal interactions may occur: none known.

Before using this medication, tell your doctor or pharmacist of all prescription and non-prescription/herbal products you may use, especially of:

This information does not contain all possible interactions. Therefore, before using hydroxocobalamin, tell your doctor or pharmacist of all the products you use.


The effects of overdose with hydroxocobalamin are not known.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of hydroxocobalamin or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.


If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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