Zafirlukast for asthma prevention (prophylaxis)

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Zafirlukast for asthma prevention (prophylaxis)

This leaflet is about the use of zafirlukast for the treatment of asthma. It is taken regularly in order to prevent attacks. (This is sometimes called asthma prophylaxis.)

Information Standard quality markThis leaflet has been written specifically for parents and carers about the use of this medicine in children. The information may differ from that provided by the manufacturer. Please read this leaflet carefully. Keep it somewhere safe so that you can read it again.

Zafirlukast should not be used during an acute asthma attack (sudden onset of wheezing and breathlessness). Use your child’s reliever medicine (usually a blue salbutamol inhaler).

In an acute asthma attack – if your child’s asthma symptoms are not getting better or they are still struggling to breathe after taking their blue salbutamol inhaler, take them to hospital straight away.

Name of drug

Brand name:

Why is it important for my child to take this medicine?

Zafirlukast belongs to a family of medicines called leukotriene receptor antagonists. Leukotrienes can cause inflammation in the lungs, which can act as a trigger for asthma. Zafirlukast blocks this effect and so should reduce the number of attacks of wheezing or coughing. Your doctor will probably recommend that you continue to give your child their steroid inhaler.

Zafirlukast will not reduce wheezing or breathlessness during an acute asthma attack – your child should use their ‘reliever’ inhaler for this (this is often a blue salbutamol inhaler).

What is zafirlukast available as?

Tablets: 20 mg; these contain small amounts of lactose

When should I give zafirlukast?

Zafirlukast is usually given twice each day, once in the morning and once in the evening. Ideally, these times are 10–12 hours apart, for example some time between 7 and 8 am, and between 7 and 8 pm.

How much should I give?

Your doctor will work out the amount of zafirlukast (the dose) that is right for your child. The dose will be shown on the medicine label.

It is important that you follow your doctor’s instructions about how much to give.

How should I give it?

TabletsTablets should be swallowed with a glass of water, milk or juice. Your child should not chew the tablet.

When should the medicine start working?

Zafirlukast usually needs to be given with your child’s steroid inhaler to prevent asthma and wheeze. It does not work straight away but your child should start to wheeze less and to need less reliever medicine a few weeks after starting treatment. Continue to give the medicine twice each day, as told to by your doctor or nurse, even if your child does not have any wheeze or symptoms of asthma.

If your child’s asthma does not seem to be getting any better or they still need to use their reliever medicine often, contact your doctor or asthma nurse.

What if my child is sick (vomits)?

  • If your child is sick less than 30 minutes after having a dose of zafirlukast, give them the same dose again.
  • If your child is sick more than 30 minutes after having a dose of zafirlukast, you do not need to give them another dose. Wait until the next normal dose.

What if I forget to give it?

If you remember up to 4 hours after you should have given a dose, give your child the missed dose. For example, if you usually give a dose at about 7 am, you can give the missed dose at any time up to 11 am. If you remember after that time, do not give the missed dose. Wait until the next normal dose.

Never give a double dose of zafirlukast.

What if I give too much?

You are unlikely to do harm if you give an extra dose of zafirlukast by mistake. If you think you may have given your child too much zafirlukast, contact your doctor or NHS Direct (0845 4647 in England and Wales; 08454 24 24 24 in Scotland). Have the medicine or packaging with you if you telephone for advice.

Are there any possible side-effects?

We use medicines to make our children better, but sometimes they have other effects that we don’t want (side-effects).

Side-effects you must do something about

If your child is more short of breath or is wheezing more than usual, or their face, lips or tongue start to swell, or they develop a rash, they may be allergic to zafirlukast. Take your child to hospital or call an ambulance straight away.

Other side-effects you need to know about

The following side-effects should get better after a week. If they don’t, or you are worried, contact your doctor.

  • Your child may get stomach ache or stomach cramps or feel sick (nausea) or be sick (vomit). Giving the medicine with some food or milk may help.
  • Your child may get a headache (they may say their head is painful or pounding).

There may, sometimes, be other side-effects that are not listed above. If you notice anything unusual and are concerned, contact your doctor.

Can other medicines be given at the same time as zafirlukast?

  • You can give your child medicines that contain paracetamol or ibuprofen, unless your doctor has told you not to.
  • Check with your doctor or pharmacist before giving any other medicines to your child. This includes herbal or complementary medicines.

Is there anything else I need to know about this medicine?

  • If your child has also been prescribed a steroid inhaler, it is important that they continue to use this as your doctor has told you to, while taking zafirlukast.

General advice about medicines

  • Try to give medicines at about the same times each day, to help you remember.
  • If you are not sure a medicine is working, contact your doctor but continue to give the medicine as usual in the meantime. Do not give extra doses, as you may do harm.
  • Only give this medicine to your child. Never give it to anyone else, even if their condition appears to be the same, as this could do harm.

If you think someone else may have taken the medicine by accident, contact your doctor straight away.

  • Make sure that you always have enough medicine. Order a new prescription at least 2 weeks before you will run out.
  • Make sure that the medicine you have at home has not reached the ‘best before’ or ‘use by’ date on the packaging. Give old medicines to your pharmacist to dispose of.

Where should I I keep this medicine?

  • Keep the medicine in a cupboard, away from heat and direct sunlight. It does not need to be kept in the fridge.
  • Make sure that children cannot see or reach the medicine.
  • Keep the medicine in the container it came in.

Who to contact for more information

Your child’s doctor, pharmacist or nurse will be able to give you more information about zafirlukast and about other medicines used to manage asthma.

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