• Keep this leaflet.You may need to read it again.
• If you have any further questions, ask your doctor or nurse.
• In this leaflet, Cytamen® 1000 micrograms/ml Solution for Injection will be called Cytamen.

1. What Cytamen is for
2. Before you are given Cytamen
3. How you will be given Cytamen
4. Possible side effects
5. How to store Cytamen
6. Further information.

• You are allergic to the active ingredient, cyanocobalamin
• You are allergic to any of the other ingredients of Cytamen (see section 6.)
• You have a condition called toxic amblyopia (poor vision which may be due to Vitamin B12 deficiency).

If any of the above applies to you talk to your doctor or nurse.

• You are pregnant, planning to become pregnant or breast-feeding
• You have megaloblastic anaemia. This is a blood disorder where you have larger than normal blood cells

• Antibiotics (for treating infections) or antimetabolites (medicines which stop cells dividing, such as mercaptopurine for leukaemia), as these treatments may interfere with tests to measure the levels of Vitamin B12 in your blood or urine
• An antibiotic called chloramphenicol, as you may not respond well to Cytamen
• Oral contraceptives 'The Pill'
• Any other medicine, including medicines obtained without a prescription.

If any of the above applies to you talk to your doctor or nurse.

Cytamen should not be used in pregnancy for treating a kind of anaemia called megaloblastic anaemia, unless you also have a Vitamin B12 deficiency.

Cytamen is found in breast-milk but it is unlikely that it will harm your baby.

If you are pregnant, trying to become pregnant or are breast-feeding, ask your doctor or nurse for advice before being given Cytamen.

Cytamen may cause dizziness. If this happens to you, do not drive or use machinery.

This medicine contains less than 1mmol (23mg) sodium per dose, that is to say essentially ‘sodium-free’.

Your doctor will choose the dose that is right for you.

You will be given Cytamen by your doctor or nurse as an injection into a muscle. You may be given it just once or it may be repeated every other day, weekly or monthly, depending on how much your body needs.

• Treatment of anaemia:
  • Without neurological (nervous system) involvement: Initially 250 – 1000 micrograms, every other day for 1 to 2 weeks, then 250 micrograms weekly until the blood tests are normal.
  • Maintenance dose: 1000 micrograms every month.
  • With neurological involvement: 1000 micrograms every other day for as long as improvement is noticed.
    Maintenance dose: 1000 micrograms every month.
• Prevention of anaemia:
  • 250 -1000 micrograms every month.
• Schilling Test:
  • 1000 micrograms.

While you are receiving this medicine, your doctor will want you to have regular blood tests to check your condition. This is to make sure that your medicine is working properly and that the dose you are receiving is right for you.

If you think you have been given too much Cytamen, you are unlikely to need any special treatment. However, if you suffer any discomfort or side effects you should tell your doctor.

This includes any of the following symptoms:

• Difficulties in breathing
• Swelling of your eyelids, face or lips
• Rash or itching especially those covering your whole body
• Collapse.

Effects on the heart and blood

• Low blood potassium levels and irregular heart beat during the early stages of treatment
• Thrombocytosis (where you have a high number of platelets in your blood)

Effects on the eyes and skin

• Acne-like rash
• Blisters
• Pain at the site of injection
• The skin may become hard at the site of injection
• The skin around the injection site may die.

Effects on the stomach and bowel

• Feeling unwell or sick

Effects on the nervous system

• Dizziness
• Tremor

• Fever
• Chills
• Hot flushes
• Pain.

If you get any side effects, talk to your doctor or nurse. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via Yellow Card Scheme Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store. By reporting side effects you can help provide more information on the safety of this medicine.

The active substance is cyanocobalamin at a strength of 1000 micrograms (1 mg) per ml of solution.

The other ingredients are sodium chloride, acetic acid and water for injection.

Cytamen® 1000 micrograms/ml Injection is a sterile solution.

It comes in packs of 5 ampoules, each containing 1 ml of solution.