This information is intended for use by health professionals

1. Name of the medicinal product

Neo-Cytamen 1000 micrograms/ml solution for injection

Hydroxocobalamin 1000 micrograms/ml solution for injection

2. Qualitative and quantitative composition

Hydroxocobalamin chloride 1.027mg equivalent to 1.0 mg Hydroxocobalamin.

For excipients, see 6.1

3. Pharmaceutical form

Solution for injection.

4. Clinical particulars
4.1 Therapeutic indications

Addisonian pernicious anaemia.

Prophylaxis and treatment of other macrocytic anaemias associated with vitamin B12 deficiency.

Tobacco amblyopia and Leber's optic atrophy.

4.2 Posology and method of administration

Route of administration: Intramuscular.

Adults and Children

Addisonian pernicious anaemia and other macrocytic anaemias without neurological involvement:

Initially: 250 to 1000mcg intramuscularly on alternate days for one to two weeks, then 250mcg weekly until the blood count is normal.

Maintenance: 1000mcg every two to three months.

Addisonian pernicious anaemia and other macrocytic anaemias with neurological involvement:

Initially: 1000mcg on alternate days as long as improvement is occurring.

Maintenance: 1000mcg every two months.

Prophylaxis of macrocytic anaemia associated with vitamin B12 deficiency resulting from gastrectomy, some malabsorption syndromes and strict vegetarianism:

1000mcg every two to three months.

Tobacco amblyopia and Leber's optic atrophy:

Initially: 1000mcg or more daily by intramuscular injection for two weeks. Then twice weekly as long as improvement is occurring.

Maintenance: 1000mcg monthly.

4.3 Contraindications

Hypersensitivity to any ingredient of the preparation.

Neo-Cytamen should not be used for treatment of megaloblastic anaemia of pregnancy unless vitamin B12 deficiency has been demonstrated.

4.4 Special warnings and precautions for use


The dosage schemes given above are usually satisfactory, but regular examination of the blood is advisable. If megaloblastic anaemia fails to respond to hydroxocobalamin, folate metabolism should be investigated. Doses in excess of 10mcg daily may produce a haematological response in patients with folate deficiency. Indiscriminate administration may mask the true diagnosis. The haematological and neurological state should be monitored regularly to ensure adequacy of therapy. Cardiac arrhythmias secondary to hypokalaemia during initial therapy have been reported. Plasma potassium should therefore be monitored during this period. Platelet count should be monitored during the first weeks of use in megaloblastic anaemia due to the possible occurrence of reactive thrombocytosis.

4.5 Interaction with other medicinal products and other forms of interaction

Chloramphenicol-treated patients may respond poorly to Neo-Cytamen. Serum concentrations of hydroxocobalamin may be lowered by oral contraceptives but this interaction is unlikely to have clinical significance. Antimetabolites and most antibiotics invalidate vitamin B12 assays by microbiological techniques.

4.6 Pregnancy and lactation

Neo-Cytamen should not be used for the treatment of megaloblastic anaemia of pregnancy unless vitamin B12 deficiency has been demonstrated. Neo-Cytamen is secreted into breast milk but this is unlikely to harm the infant, and may be beneficial if the mother and infant are vitamin B12 deficient.

4.7 Effects on ability to drive and use machines

None stated.

4.8 Undesirable effects

The following effects have been reported and are listed below by body system:

Blood and lymphatic system disorders

Reactive thrombocytosis can occur during the first weeks of use in megaloblastic anaemia.

Cardiovascular disorders:

Arrhythmias secondary to hypokalaemia.

Disorders of the immune system:

Hypersensitivity reactions including skin reactions (e.g. rash, itching) and exceptionally anaphylaxis.

Gastro intestinal disorders:

Nausea, vomiting, diarrhoea.

General disorders:

Fever, chills, hot flushing, dizziness, malaise, pain. Injection site reactions including injection site pain, injection site erythema, injection site pruritus, injection site induration, and injection site swelling.

Neurological disorders:

Headache, sensory abnormalities such as paraesthesiae.


Renal and unrinary disorders:


Skin and subcutaneous tissue disorders:

Acneiform and bullous eruptions.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via Yellow Card Scheme Website or search for MHRA Yellow Card in the Google Play or Apple App Store.

4.9 Overdose

Treatment is unlikely to be needed in cases of overdosage.

5. Pharmacological properties
5.1 Pharmacodynamic properties

Neo-Cytamen contains Hydroxocobalamin, one of the forms of vitamin B12.

5.2 Pharmacokinetic properties

An intramuscular injection of hydroxocobalamin produces higher serum levels than the same dose of cyanocobalamin, and these levels are well maintained.

After injection of hydroxocobalamin, 90% of a 100 microgram dose and 30% of a 1000 microgram dose are retained. Vitamin B12 is extensively bound to specific plasma proteins called transcobalamins; transcobalamin II appears to be involved in the rapid transport of the cobalamins to tissues. Vitamin B12 is stored in the liver, excreted in the bile, and undergoes extensive enterohepatic recycling; part of an administered dose is excreted in the urine, most of it in the first 8 hours; urinary excretion, however, accounts for only a small fraction in the reduction of total body stores acquired by dietary means. Vitamin B12 diffuses across the placenta and also appears in breast milk.

5.3 Preclinical safety data

None stated.

6. Pharmaceutical particulars
6.1 List of excipients

Sodium chloride, acetic acid, Water for Injections.

6.2 Incompatibilities


6.3 Shelf life

36 months.

6.4 Special precautions for storage

Protect from light. Do not store above 25°C.

6.5 Nature and contents of container

1ml clear, one-point cut (OPC) glass Type 1 Ph Eur ampoules packed in cartons of 5 ampoules

6.6 Special precautions for disposal and other handling

Not applicable.

7. Marketing authorisation holder

RPH Pharmaceuticals AB

Box 603

101 32 Stockholm


8. Marketing authorisation number(s)


9. Date of first authorisation/renewal of the authorisation

14/10/1992 / 21/01/2004

10. Date of revision of the text