Cytarabine 100 mg / ml injection – patient leaflet, side effects, dosage

1. What Cytarabine is and what it is used for

Cytarabine is an anti‑cancer medicine. Treatment with an anti‑cancer medicine is sometimes called cancer chemotherapy.

This medicine is used to treat some types of leukaemia (cancer affecting the blood) and lymphomas (cancer of the lymph glands). It may be used in combination with other anti‑cancer medicines.

You must talk to a doctor if you do not feel better or if you feel worse.

2. What you need to know before you use Cytarabine

Do not use Cytarabine

• if you are allergic to cytarabine or any of the other ingredients of this

  medicine (listed in section 6)

• if your blood cell count (number of cells in your blood) is very low due

  to some cause other than cancer (unless your doctor decides the benefits of treatment outweigh the risks)

• if you have had severe effects on your brain (encephalopathy) after

  radiation treatment or treatment with another anticancer medicine such as methotrexate

• if you are pregnant (unless your doctor considers the benefits to the

  mother outweigh the risks to the unborn child)

Tell your doctor if you think any of the above applies to you before this medicine is used.

Warnings and precautions

Talk to your doctor or pharmacist before using Cytarabine. Cytarabine can have toxic effects on the body so this medicine will be given to you in a hospital by a doctor experienced in cancer chemotherapy. The main toxic effect is bone marrow suppression which can reduce immunity, make it more difficult for oxygen to be carried around the body and affect blood clotting. Less serious toxicity includes being sick, feeling sick, diarrhoea, stomach pain, mouth ulcers, and liver problems. Take special care with Cytarabine

• if your blood cell count is low

• if you have any problems with your liver including jaundice (causes

  yellowing of the skin)

• if you have any problems with your kidneys

  • if you have recently received cancer medicine treatment or

    radiotherapy or if you are due to have radiotherapy (the side effects of radiotherapy can be made worse by cytarabine treatment) • cytarabine strongly reduces blood cell production in the bone marrow

    and your blood cell numbers can continue to fall for up to a week after stopping treatment. Your doctor will test your blood regularly and examine your bone marrow if required

  • if your bone marrow is still recovering from the effects of other

    medicines (your doctor will only consider treatment with this medicine if absolutely necessary)

  • serious and sometimes life‑threatening side effects can occur in the

    central nervous system, the bowels, the lungs or the heart especially when treated with high doses of cytarabine

  • the levels of uric acid (showing that the cancer cells are destroyed) in

    your blood (hyperuricemia) may be high during treatment. Your doctor will tell you if you need to take any medicine to control this • during treatment with cytarabine administration of certain vaccines is

    not advised. If required, consult your doctor. Use of killed or inactivated vaccine may not have the desired effect due to suppressed immune system while on this medicine

  • during treatment with cytarabine, granulocyte transfusion should be

    avoided as severe breathing problems have been reported. Your doctor will determine if this treatment is required

  • during treatment with other drugs acute pancreatitis has occurred, tell

    your doctor if you have pain in the stomach

Tell your doctor if any of the above applies to you before this medicine is used. Your doctor will monitor your blood to check your blood cell count, and your liver and kidney functions to check for raised uric acid levels. Children

Special care will be taken if Cytarabine is to be given to a child. This medicine should not be used in infants.

Other medicines and Cytarabine

Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicines. This is important because some medicines can interact with cytarabine and may require special care. The effectiveness of the following medicines may be reduced or increased by cytarabine:

• methotrexate (a medicine used to treat a range of cancers and some

  inflammatory conditions)

• digoxin or beta‑acetyl digoxin tablets (heart medicine) • gentamicin (an antibiotic)

• 5‑fluorocytosine (a medicine used to treat fungal infections) • medicines containing cyclophosphamide, vincristine and prednisone

  which are used in cancer treatment programmes

• other medicines which decrease the activity of the immune system Pregnancy, breast-feeding and fertility

If you are pregnant or breast‑feeding, think you may be pregnant or are planning to have a baby, ask your doctor or pharmacist for advice before taking this medicine.

Contraception in women of childbearing potential

Women should always use highly effective birth‑control (contraception) to prevent pregnancy during treatment and for 6 months after the last dose. Talk to your doctor about birth control methods that are right for you and your partner.

Contraception in men

Male patients with female partners of reproductive potential should always use highly effective contraception to prevent pregnancy during treatment and for 3 months after the last dose.

Pregnancy

Because of the potential for abnormalities with cytarabine therapy, particularly during the first trimester, if you are or may become pregnant, talk to your doctor or pharmacist about the potential risk to the foetus.

Breast‑feeding

You should stop breast‑feeding for the duration of cytarabine therapy and for at least one week after the last dose because this medicine may be harmful to infants being breast‑fed.

Ask your doctor or pharmacist for advice before taking any medicine. Driving and using machines

Do not drive or use machines if you experience any side effect which may lessen your ability to do so.

Cytarabine contains sodium

Cytarabine 100 mg/ml Injection contains less than 1 mmol sodium (23 mg) in each vial, that is to say essentially ‘sodium‑free’.

3. How to use Cytarabine

This medicine may be given by injection (using a syringe) under the skin (subcutaneous or ‘SC’) or into a vein (intravenous or ‘IV’). It may also be given by infusion (drip) into a vein. If given as an infusion, Cytarabine will be diluted first.

Cytarabine 100 mg/ml Injection must not be injected intrathecally (into the spine).

Recommended Dose

Your doctor will work out the correct dose of cytarabine for you and how often it must be given.

The dose will depend on your medical condition, your size and how well your liver is working. Your doctor will tell you how well your liver is working using blood tests.

You will have regular blood tests after your dose of Cytarabine to check for side effects. These tests may be done more often if you are elderly, as you may be more likely to get side effects. Treatment may have to be stopped if your blood cell count drops too low.

If you use more Cytarabine than you should

This medicine will be given to you in a hospital, under the supervision of a doctor. It is unlikely that you will be given too much or too little, however, tell your doctor or nurse if you have any concerns.

4. Possible side effects

Like all medicines, this medicine can cause side effects, although not everybody gets them.

If any of the following happen, tell your doctor or nursing staff immediately:

• sore mouth, particularly if you have several ulcers inside of the mouth • severe allergic reaction ‑ you may experience a sudden itchy rash

  (hives), swelling of the hands, feet, ankles, face, lips, mouth or throat (which may cause difficulty in swallowing or breathing), and you may feel you are going to faint

• symptoms of an infection, e.g. fever, chills, aches or soreness when

  swallowing

• unexpected bleeding e.g. bleeding gums, blood in urine or vomit,

  unexpected bruises

• black tarry stools which may indicate bleeding in the digestive system • severe pain in the chest and difficulty breathing (this may be a

  symptom of pericarditis)

• severe pain in the abdomen (this may be a symptom of inflammation of

  the pancreas)

• loss of vision, loss of sense of touch, mental disturbance or loss of

  ability to move normally (this medicine may cause side effects to the brain and eyes which are usually reversible but may be very serious) These are serious side effects. You may need urgent medical attention. If you experience any of the following tell your doctor as soon as possible:

The side effects of cytarabine are dependent on the dose. The digestive tract is most commonly affected, but also the blood.

Cytarabine 100 mg/ml Injection The following information is intended for medical or healthcare professionals only

Further to the information included in section 3, practical information on the preparation/handling of the medicinal product is provided here. Cytarabine 100 mg/ml Injection should not be administered by the intrathecal route due to the slight hypertonicity of this formulation.

Incompatibilities

Solutions of cytarabine have been reported to be incompatible with various drugs, i.e. carbenicillin sodium, cephalothin sodium, fluorouracil, gentamicin sulfate, heparin sodium, hydrocortisone sodium succinate, insulin‑regular, methylprednisolone sodium succinate, nafacillin sodium, oxacillin sodium, penicillin G sodium. However, incompatibility depends on several factors (e.g. concentrations of the drug, specific diluents used and resulting pH, temperature). Specialised references should be consulted for specific compatibility information.

Use and handling

Do not refrigerate or freeze.

Cytarabine 100 mg/ml Injection is a ready to use solution, but it can be diluted with Water for Injections BP, Glucose Intravenous Infusion BP or Sodium Chloride Intravenous Infusion BP.

Chemical and physical in‑use stability has been demonstrated for 7 days at room temperature.

From a microbiological point of view, the product should be used immediately. If not used immediately, in‑use storage times and conditions prior to use are the responsibility of the user and would normally not be longer than 24 hours unless dilution has taken place in controlled and validated aseptic conditions.

Prior to use, vials of Cytarabine 100 mg/ml Injection must be warmed to 55°C, for 30 minutes, with adequate shaking, and allowed to cool to room temperature.

2026-1000160G Very common: may affect more than 1 in 10 people

• whole body infection (sepsis) seen as a fever, vomiting, confusion,

  dizziness, chills

• lung infection

• infection (viral, bacterial, fungal, parasitic, saprophytic), in any location

  of the body

• bone marrow failure
• abnormal liver function
• rash
• reduction in the amount of red blood cells
• balance and co‑ordination difficulties
• slurred speech, vocal changes
• sleepiness
• severe shortness of breath, rapid, shallow breathing • tiredness, drowsiness or confusion
• feeling faint
• a cough that produces sputum that may have blood in it • cold, clammy skin

Sometimes the following side effects can occur together, usually 6‑12 hours after receiving cytarabine:

• feeling generally unwell with a high temperature
• pain in bone, muscle and occasionally the chest
• rash
• sore eyes

This is known as ‘cytarabine syndrome’ and it can be treated. If you experience these side effects, please tell your doctor or nurse as soon as possible. Common: may affect up to 1 in 10 people

• decrease in cells responsible for providing immunity, carrying oxygen

  around the body and for normal blood clotting shown as a reduction in the amount of red and white cells and platelets in the blood, anaemia, shortness of breath, unexpected bleeding e.g. bleeding gums, blood in urine or vomit, unexpected bruises

• abnormal blood cells (megaloblastosis)
• loss of appetite

• high levels of uric acid in your blood due to the breakdown of cancer

  cells during treatment with cytarabine (your doctor will monitor for this) • reduced consciousness, speaking difficulties, abnormal eye

  movements (nystagmus)

• reversible effects on the eyes such as sore eyes with bleeding

  (haemorrhagic conjunctivitis), vision disturbance, sensitivity to light (photophobia), watery or burning eyes and inflammation of the surface of the eye (cornea) (keratitis)

• feeling or being sick, diarrhoea, sores or ulcers of the mouth or anus

  (back passage), mild pain in the abdomen

• reversible effects on the liver such as increased enzyme levels • reversible effects to the skin such as reddening (erythema), blistering,

  rash, hives, blood vessel inflammation (vasculitis), skin dryness, itching • hair loss

• impaired/disturbed kidney function, problems passing urine • fever
• blood clots causing inflammation at the site of injection Uncommon: may affect up to 1 in 100 people
• headache

• numbness or weakness of the arms and legs, paralysis of the legs and

  lower body when cytarabine is given into the space surrounding the spinal cord (intrathecal)

• inflammation of the sac that surrounds the heart
• shortness of breath
• sore throat

• inflammation of the food pipe (oesophagus), ulcers in the food pipe • bowel cysts (pneumatosis cystoides intestinalis), severe bowel

  inflammation (necrotising colitis), serious infection of the membrane that lines the abdomen (peritonitis)

• brown/black spots on the skin (lentigo), ulceration of the skin, itching • painful redness and blistering on the hands and the soles of the feet • joint and muscle pain

  Very rare: may affect up to 1 in 10,000 people

  • irregular heartbeat (arrhythmia)

Not known: frequency cannot be estimated from the available data

• low counts of pre‑stages of red cells in the blood (reticulocytopenia) • serious allergic reaction causing difficulty breathing or swelling of the

  face or throat

• dizziness, inflammation of a nerve or part of the nervous system,

  damage to nerve tissues and pain

• sore or itchy eyes

• black tarry stools which may indicate bleeding in the digestive system • inflammation of the pancreas which may cause severe pain in the

  abdomen and back

• yellowing of the skin or yellowing of the whites of the eyes (jaundice) • skin rash, pigmented spots on the skin (freckles), skin bleeding,

  tightness of skin and sensation of tingling

• redness, pain or swelling of the ears that may occur during or shortly after

  cytarabine treatment (known as “Ara‑C ears” or auricular erythema) • inflammation of sweat glands, sometimes causing tender red patches

  on the skin (called neutrophilic eccrine hidradenitis)

• lack of periods and low sperm count (amenorrhoea and azoospermia) • chest pain
• irritation or infection at the site of injection
• bleeding of the lining of the mouth
• slower heartbeat
• liver abscess
• personality change
• coma
• convulsions
• uncontrollable movements
• shaking
• confusion
• inflammation at the site of injection
• corneal lesion

The side effects on the digestive tract are less if cytarabine is given by infusion rather than by bolus injection. Your doctor may prescribe local corticosteroids (anti‑inflammatory medicines) to prevent or reduce effects on the eyes such as sore eyes with bleeding (haemorrhagic conjunctivitis). This medicine may lead to changes in your blood cells. Your doctor will take blood samples to monitor for these and also to check how well your liver and kidneys are working.

Reporting of side effects

If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme at: 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.

5. How to store Cytarabine

Keep this medicine out of the sight and reach of children. Expiry

Do not use this medicine after the expiry date which is stated on the vial and carton after 'EXP'. The expiry date refers to the last day of that month. Storage

Do not store above 25°C. Keep the vial in the outer carton in order to protect from light.

Do not refrigerate or freeze.

Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.

6. Contents of the pack and other information

What Cytarabine contains

The active substance is cytarabine. Each millilitre (ml) of solution contains 100 milligrams (mg) of cytarabine.

The other ingredients (excipients) are water for injections, hydrochloric acid and sodium hydroxide.

What Cytarabine looks like and contents of the pack

Cytarabine 100 mg/ml Injection is a clear, colourless solution for injection which comes in glass containers called vials. It may be supplied in packs containing:

1, 5, 10 or 20 x 100 mg/1 ml vials

1, 5, 10 or 20 x 500 mg/5 ml vials

1, 5, 10 or 20 x 1 g/10 ml vials

1, 5, 10 or 20 x 2 g/20 ml vials

Not all pack sizes may be marketed.

Marketing Authorisation Holder

Hospira UK Limited

Walton Oaks

Walton‑On‑The‑Hill

Dorking Road

Tadworth

Surrey

KT20 7NS

UK

Manufacturer

Pfizer Service Company BV

Hermeslaan 11

1932 Zaventem

Belgium

This leaflet was last revised in 08/2026.

Ref: gxCY 21_0

GUJ‑DRUGS/G/28/1267

2026-1000160G