How does hydroxocobalamin work?
Hydroxocobalamin is a manufactured version of vitamin B12.
It works by increasing your levels of vitamin B12 so that you can make red blood cells that work properly to carry oxygen around your body.
This helps to reduce symptoms such as tiredness and lack of energy.
When will I feel better?
Hydroxocobalamin starts to work straight away. However, it may take a few days or weeks before your vitamin B12 levels and symptoms (such as extreme tiredness or lack of energy) start to improve.
Are there any long-term side effects?
It's OK to have hydroxocobalamin injections for a long time. Some people will need to have them for the rest of their lives.
What will happen if I stop having the injections?
You'll be given appointments for your hydroxocobalamin injections.
If you miss having your injection, the level of vitamin B12 in your body will go down even more. This may make your health problems worse.
Talk to your doctor if you want to stop having hydroxocobalamin injections or if you are bothered by side effects.
Will it affect my contraception?
Hydroxocobalamin will not stop any type of contraception working, including the combined pill, progestogen-only pill and emergency contraception.
Contraceptive pills may reduce the levels of hydroxocobalamin in your blood, but this will not affect your treatment.
However, if hydroxocobalamin makes you sick (vomit) or have severe diarrhoea for more than 24 hours, your contraceptive pills may not protect you from pregnancy.
Find out more:
Can I drive or ride a bike?
Hydroxocobalamin generally does not affect your ability to drive or ride a bike.
However, it can make some people feel dizzy. If you feel dizzy after having it, do not drive, cycle or use any machinery or tools until you feel OK again.
It's an offence to drive a car if your ability to drive safely is affected. It's your responsibility to decide if it's safe to drive. If you're in any doubt, do not drive.
Talk to your doctor if you're unsure whether it's safe for you to drive while having hydroxocobalamin. GOV.UK has more information on the law on drugs and driving.
Can I drink alcohol while having hydroxocobalamin?
Yes, you can drink alcohol while having hydroxocobalamin. Alcohol does not affect how this medicine works.
However, drinking too much on a regular basis can cause folate deficiency anaemia.
Try not to drink more than 14 units of alcohol a week. A standard glass of wine (175ml) is 2 units. A pint of lager or beer is usually 2 to 3 units of alcohol.
Is there any food or drink I need to avoid?
You can eat and drink normally while having hydroxocobalamin.