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Drug Class: Commonly Known As: Category:
Immunological Agent Xolair™ Adult, Children

Omalizumab - What is it for

Omalizumab is a synthetic protein that is similar to natural proteins produced by the body. It is used for the treatment of allergic asthma and chronic spontaneous urticaria (CSU) in adults and adolescents (12 years of age and older). Omalizumab works by blocking a substance called immunoglobulin E (IgE), which is produced by the body. IgE plays a key role in causing allergic asthma or CSU.

Allergic asthma

It is used to prevent asthma from getting worse by controlling symptoms of severe allergic asthma in those who are already receiving asthma medicine, but whose asthma symptoms are not well controlled by medicines such as high-dose steroid inhalers or beta-agonist inhalers.

Do note that Omalizumab does not treat acute asthma symptoms, such as a sudden asthma attack. Therefore, Omalizumab should not be used to treat such symptoms.

Chronic spontaneous urticaria (CSU)

It is used to treat CSU in those who are already receiving antihistamines, but whose symptoms are not well-controlled by these medicines.

Do note that Omalizumab is not meant to prevent or treat other allergy-type conditions, such as food allergy or hay fever.

Omalizumab - Side Effects, Precautions, and Contraindications

What side effects can Omalizumab cause?

Like all medicines, this medicine can cause side effects, although not everybody gets them. The side effects caused by omalizumab are usually mild to moderate but can occasionally be serious.

Common side effects:

  • Fever

  • Reactions at the injection site including pain, swelling, itching and redness

  • Pain in the upper part of the tummy

  • Headache

Uncommon side effects

  • Feeling dizzy, sleepy or tired

  • Tingling or numbness of the hands or feet

  • Fainting, low blood pressure while sitting or standing (postural hypotension), flushing

  • Sore throat, coughing, acute breathing problems

  • Feeling sick (nausea), diarrhoea, indigestion

  • Itching, hives, rash, increased sensitivity of the skin to sun

  • Weight increase

  • Flu-like symptoms

  • Swelling arms

Serious, but rare side effects:

  • Sudden severe allergic reactions: if you notice any serious sudden signs of allergy or combination of signs such as rash, itching or hives on the skin, swelling of the face, lips, tongue, larynx (voice box), windpipe or other parts of the body, fast heartbeat, dizziness and lightheadedness, shortness of breath, wheezing or trouble breathing, or any other new symptoms, tell your doctor or nurse immediately.

  • Development of one or more of the following symptoms: swelling, pain or rash around blood or lymph vessels, high level of a specific type of white blood cells (marked eosinophilia), worsening problems with breathing, nasal congestion, heart problems, pain, numbness, tingling in the arms and legs (signs of “Churg-Strauss syndrome or hypereosinophilic syndrome”).

  • Low blood platelet count with symptoms such as bleeding or bruising more easily than normal.

  • Development of any of the following symptoms, especially if in combination: joint pain with or without swelling or stiffness, rash, fever, swollen lymph nodes, muscle pain (signs of serum sickness).

If you or your child experience any of these, tell your doctor or nurse straight away.

Before taking Omalizumab, what precautions must I follow?

Talk to your doctor before you or your child is given Omalizumab:

  • If you or your child is allergic to omalizumab or any of the other ingredients of this medicine (L-arginine hydrochloride, L-histidine hydrochloride, L-histidine, Polysorbate 20 and latex).
  • If you or your child have kidney or liver problems.
  • If you or your child have a disorder where your own immune system attacks parts of the body (autoimmune disease).
  • If you or your child is travelling to such a region where infections caused by parasites are common as Omalizumab may weaken body's resistance to such infections.

What food or medicine must I avoid when I take Omalizumab?

Omalizumab - Dosage and How to Use

How should Omalizumab be used?

Your doctor will work out how much Omalizumab you or your child need, and how often you or your child will be given it. This depends on the body weight and the results of a blood test carried out before the start of the treatment to measure the amount of IgE in the blood.

Omalizumab will be given to you or your child by a doctor or nurse as an injection under the skin (subcutaneously).

You or your child may be given 1 to 4 injections at a time, either every two weeks, or every four weeks.

Ensure that you or your child continues to take the current medicines during Omalizumab treatment. Do not stop taking any medicines without talking to your doctor.

You may not see an immediate improvement in your or your child's asthma or CSU after beginning Omalizumab therapy. It usually takes between 12 and 16 weeks to have the full effect.

What should I do if I miss a dose?

Contact your doctor or hospital as soon as possible to re-schedule your appointment.

What should I do if I overdose?

Omalizumab - Handling and Storage

How should I handle Omalizumab safely?

How should I store Omalizumab?

Keep away from children;#Keep in a cool, dry place, away from direct sunlight;#Store in the refrigerator. Do not freeze.;#

How should I dispose of Omalizumab safely?

Omalizumab - Additional Information

Tell your doctor, pharmacist or nurse if you or your child is taking, has recently taken or might take any other medicines. This is especially important if you or your child is taking medicines to treat an infection caused by a parasite, as Omalizumab may reduce the effect of the medicines.

Do not stop Omalizumab treatment unless your doctor tells you to. Interrupting or stopping treatment with Omalizumab may cause your or your child's symptoms to come back.

  • Updated on Wednesday, October 4, 2017
  • This article is contributed by Pharmacy Department KK Women's and Children's Hospital

    The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth

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