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Active substance: MONTELUKAST SODIUM

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SINGULAIR® 10 mg Tablets/
MONTELUKAST 10 mg Tablets


(montelukast sodium)

Patient Information Leaflet
This medicine is available in either of the above
names but will be referred to as Singulair
throughout the following:
Read all of this leaflet carefully before you
start taking this medicine.
• Keep this leaflet. You may need to read it
• If you have any further questions, please ask
your doctor or pharmacist.
• This medicine has been prescribed for you.
Do not pass it on to others. It may harm them,
even if their symptoms are the same as
• If any of the side effects gets serious, or if you
notice any side effects not listed in this
leaflet, please tell your doctor or pharmacist.
In this leaflet:
1. What Singulair is and what it is used for
2. Before you take Singulair
3. How to take Singulair
4. Possible side effects
5. How to store Singulair
6. Further information

• Any patient on anti-asthma medicines should
be aware that if you develop a combination of
symptoms such as a flu-like illness, pins and
needles or numbness of arms or legs,
worsening of pulmonary symptoms, and/or
rash, you should consult your doctor.
• You should not take acetyl-salicylic acid
(aspirin) or anti-inflammatory medicines
anti-inflammatory drugs or NSAIDs) if they
make your asthma worse.
Use in children
For children 2 to 5 years old, Singulair
Paediatric 4 mg chewable tablets and Singulair
Paediatric 4 mg granules are available.
For children 6 to 14 years old, Singulair
Paediatric 5 mg chewable tablets are available.
Taking other medicines
Some medicines may affect how Singulair
works, or Singulair may affect how other
medicines work.

1. What Singulair is and what it is used for

Please tell your doctor or pharmacist if you are
taking or have recently taken other medicines,
including those obtained without a prescription.

Singulair is a leukotriene receptor antagonist
that blocks substances called leukotrienes.
Leukotrienes cause narrowing and swelling of
airways in the lungs and also cause allergy
symptoms. By blocking leukotrienes, Singulair
improves asthma symptoms, helps control
asthma and improves seasonal allergy
symptoms (also known as hay fever or
seasonal allergic rhinitis).

Tell your doctor if you are taking the following
medicines before starting Singulair:
• phenobarbital (used for treatment of
• phenytoin (used for treatment of epilepsy)
• rifampicin (used to treat tuberculosis and
some other infections)
• gemfibrozil (used for treatment of high lipid
levels in plasma)

Your doctor has prescribed Singulair to treat
asthma, preventing your asthma symptoms
during the day and night.
• Singulair is used for the treatment of patients
who are not adequately controlled on their
medication and need additional therapy.
• Singulair also helps prevent the narrowing of
airways triggered by exercise.
• In those asthmatic patients in whom Singulair
is indicated in asthma, Singulair can also
provide symptomatic relief of seasonal
allergic rhinitis.

Taking Singulair with food and drink
Singulair 10 mg may be taken with or without

Your doctor will determine how Singulair should
be used depending on the symptoms and
severity of your asthma.
What is asthma?
Asthma is a long-term disease.
Asthma includes:
• difficulty breathing because of narrowed
airways. This narrowing of airways worsens
and improves in response to various
• sensitive airways that react to many things,
such as cigarette smoke, pollen, cold air, or
• swelling (inflammation) in the lining of the
Symptoms of asthma include:
wheezing, and chest tightness.


What are seasonal allergies?
Seasonal allergies (also known as hay fever or
seasonal allergic rhinitis) are an allergic
response often caused by airborne pollens from
trees, grasses and weeds. The symptoms of
seasonal allergies typically may include: stuffy,
runny, itchy nose; sneezing; watery, swollen,
red, itchy eyes.

2. Before you take Singulair
Tell your doctor about any medical problems or
allergies you have now or have had.
Do not take Singulair if you
• are allergic (hypersensitive) to montelukast
or any of the other ingredients of Singulair
(see 6. Further information).
Take special care with Singulair
• If your asthma or breathing gets worse, tell
your doctor immediately.
• Oral Singulair is not meant to treat acute
asthma attacks. If an attack occurs, follow
the instructions your doctor has given you.
Always have your inhaled rescue medicine
for asthma attacks with you.
• It is important that you or your child take all
asthma medications prescribed by your
doctor. Singulair should not be substituted for
other asthma medications your doctor has
prescribed for you.

Pregnancy and breast-feeding
Use in pregnancy
Women who are pregnant or intend to become
pregnant should consult their doctor before
taking Singulair. Your doctor will assess
whether you can take Singulair during this time.
Use in breast-feeding
It is not known if Singulair appears in breast
milk. You should consult your doctor before
taking Singulair if you are breast-feeding or
intend to breast-feed.
Driving and using machines
Singulair is not expected to affect your ability to
drive a car or operate machinery. However,
individual responses to medication may vary.
Certain side effects (such as dizziness and
drowsiness) that have been reported very rarely
with Singulair may affect some patients’ ability
to drive or operate machinery.
Important information about some of the
ingredients of Singulair
Singulair 10 mg film-coated tablets contain
lactose. If you have been told by your doctor
that you have an intolerance to some sugars,
contact your doctor before taking this medicinal

3. How to take Singulair
• You should take only one tablet of Singulair
once a day as prescribed by your doctor.
• It should be taken even when you have no
symptoms or have an acute asthma attack.
• Always take Singulair as your doctor has told
you. You should check with your doctor or
pharmacist if you are not sure.
• To be taken by mouth
For adults 15 years of age and older:
One 10 mg tablet to be taken daily in the
evening. Singulair 10 mg may be taken with or
without food.
If you are taking Singulair, be sure that you do
not take any other products that contain the
same active ingredient, montelukast.
If you take more Singulair than you should
Contact your doctor immediately for advice.
There were no side effects reported in the
majority of overdose reports. The most
frequently occurring symptoms reported with
overdose in adults and children included
abdominal pain, sleepiness, thirst, headache,
vomiting, and hyperactivity.

If you forget to take Singulair
Try to take Singulair as prescribed. However, if
you miss a dose, just resume the usual
schedule of one tablet once daily.
Do not take a double dose to make up for a
forgotten dose.
If you stop taking Singulair
Singulair can treat your asthma only if you
continue to take it.
It is important to continue taking Singulair for as
long as your doctor prescribes. It will help
control your asthma.
If you have any further questions on the use of
this product, ask your doctor or pharmacist.

4. Possible side effects
Like all medicines, Singulair can cause side
effects, although not everybody gets them.
In clinical studies with Singulair 10 mg
film-coated tablets, the most commonly
reported side effects (occurring in at least 1 of
100 patients and less than 1 of 10 patients
treated) thought to be related to Singulair were:
• abdominal pain
• headache
These were usually mild and occurred at a
greater frequency in patients treated with
Singulair than placebo (a pill containing no
The frequency of possible side effects listed
below is defined using the following convention:
Very common (affects at least 1 user in 10)
Common (affects 1 to 10 users in 100)
Uncommon (affects 1 to 10 users in 1,000)
Rare (affects 1 to 10 users in 10,000)
Very rare (affects less than 1 user in 10,000)
Additionally, while the medicine has been on the
market, the following have been reported:
• upper respiratory infection (Very common)
• increased bleeding tendency (Rare)
• allergic reactions including swelling of the
face, lips, tongue, and/or throat which may
cause difficulty in breathing or swallowing
• behaviour and mood related changes
[dream abnormalities, including nightmares,
trouble sleeping, sleep walking, irritability,
feeling anxious, restlessness, agitation
including aggressive behaviour or hostility,
disturbance in attention, memory impairment
(Rare); hallucinations, disorientation, suicidal
thoughts and actions (Very rare)]
• dizziness, drowsiness, pins and needles/
numbness, seizure (Uncommon)
• palpitations (Rare)
• nosebleed (Uncommon)
• diarrhoea, nausea, vomiting (Common); dry
mouth, indigestion (Uncommon)
• hepatitis (inflammation of the liver) (Very
• rash (Common); bruising, itching, hives
(Uncommon); tender red lumps under the
skin most commonly on your shins (erythema
nodosum), severe skin reactions (erythema
multiforme) that may occur without warning
(Very rare)
• joint or muscle pain, muscle cramps
• fever
feeling unwell, swelling (Uncommon)

• Medicines should not be disposed of via
wastewater or household waste. Ask your
pharmacist how to dispose of medicines no
longer required. These measures will help to
protect the environment.

6. Further information
What Singulair contains
The active ingredient in Singulair 10mg Tablets
is montelukast. Each film-coated tablet contains
10.4mg montelukast sodium equivalent to
10mg montelukast.
The other ingredients are: Microcrystalline
cellulose, lactose monohydrate, croscarmellose
sodium, hydroxypropyl cellulose, magnesium
stearate, hypromellose, red iron oxide (E172),
yellow iron oxide (E172), titanium dioxide
(E171), and carnauba wax.
What Singulair looks like and contents of
the pack
Singulair 10mg Tablets is supplied as beige,
rounded square, film-coated tablets with
'SINGULAIR' engraved on one side, and 'MSD
117' on the other.
Singulair 10mg Tablets are available as
calendar blister pack size of 28 tablets, which
contains 4 blister strips each containing
7 tablets.
Manufacturer and Product Licence Holder
The tablets are manufactured by Merck Sharp
and Dohme Ltd., Shotton Lane, Cramlington,
Northumberland NE23 3JU, UK. It is procured
from within the EU by the Product Licence
Holder: Swinghope Limited, Brandon House,
Marlowe Way, Croydon CR0 4XS and
repackaged by Interport Limited, Brandon
House, Marlowe Way, Croydon CR0 4XS.

PL No: 10380/1140
Leaflet revision date: 27/08/2013
Singulair® is a registered trademark of Merck &
Co., Inc., USA.
Information is given by:
In UK:
Asthma UK, Providence House,
Alternatively phone the Asthma UK Advice line
on 08457 010203, Monday to Friday 9 am to 5
pm, calls charged at local rate.
In Ireland: The Asthma Society of Ireland, Eden
House, 15-17 Eden Quay, Dublin 1.
Alternatively phone The Asthma Live Line on 01
8788122, Monday, Wednesday, Thursday
10am to 1pm, or 01 8788511 9am to 5pm, or
The Asthma Line on call save 1850 44 5464.
(The Asthma UK and The Asthma Society of
Ireland are independent charities working to
conquer asthma and are not associated with
Merck Sharp & Dohme Limited.)

In asthmatic patients treated with montelukast,
very rare cases of a combination of symptoms
such as flu-like illness, pins and needles or
numbness of arms and legs, worsening of
(Churg-Strauss syndrome) have been reported.
You must tell your doctor right away if you get
one or more of these symptoms.
Ask your doctor or pharmacist for more
information about side effects. If any of the side
effects gets serious, or if you notice any side
effects not listed in this leaflet, please tell your
doctor or pharmacist.

5. How to store Singulair
• Keep out of the sight and reach of children.
• Do not store above 30°C. Store in the original
• Do not put the tablets into another container,
as they might get mixed up. Do not remove
the tablet from the calendar pack until you
are ready to take it.
• Do not take the tablets past the expiry date,
which is clearly marked on the pack.
• If the tablets become discoloured or show
signs of any deterioration, you should seek
the advice of your pharmacist who will advise
you what to do.


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Source: Medicines and Healthcare Products Regulatory Agency

Disclaimer: Every effort has been made to ensure that the information provided here is accurate, up-to-date and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This information has been compiled for use by healthcare practitioners and consumers in the United States. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective or appropriate for any given patient. If you have questions about the substances you are taking, check with your doctor, nurse or pharmacist.