Singulair Granules (Montelukast)

(℞) Prescription Required

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Singulair Granules 4mg

Product of Canada
Manufactured by: Merck Sharp & Dohme
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Singulair Granules 4mg
Product of Canada
Manufactured by Merck Sharp & Dohme
Top Brand Choice
Top Generic Choice

Montelukast Granules 4mg

Product of Canada
Manufactured by: Sandoz
*Product image for reference use only.
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Montelukast Granules 4mg
Product of Canada
Manufactured by Sandoz
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Singulair Granules (Montelukast) Dosage and Side Effects

Your physician has prescribed SINGULAIR to treat your asthma or your child's asthma, including preventing your asthma symptoms during the day and night.

Warnings and Precautions

SINGULAIR is not for the treatment of acute asthma attacks. If an attack occurs, you or your child should follow the instructions your physician has given you for that situation.

Behavior and mood-related changes have been reported in patients taking SINGULAIR. If you or your child experience these changes while taking SINGULAIR tell your physician.

BEFORE using SINGULAIR, tell your physician if you or your child:

  • have phenylketonuria;
  • suffer from liver problems;
  • are using any other medicines;
  • have or have had any medical problems or allergies.

You should immediately inform your doctor if you or your child start to have any:

  • agitation, including aggressive behaviour or hostility (such as temper tantrums in children),
  • suicidal thoughts and actions,
  • anxiousness, depression (sad mood),
  • disorientation (inability to know correct time, place or person), dream abnormalities, hallucinations (seeing or hearing things that are not there),
  • insomnia, irritability, restlessness, sleep walking,
  • tremors,
  • disturbance in attention, memory impairment.

Use in pregnancy:

Women who are pregnant or intend to become pregnant should consult their physician before taking SINGULAIR.

Use in breast-feeding:

It is not known if SINGULAIR appears in breast milk. You should consult your physician before taking SINGULAIR if you are breast-feeding or intend to breast-feed.

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.

If your or your child's asthma symptoms get worse, you should contact your physician immediately.

If your asthma is made worse by exercise, you should continue to use the medicines your physician has prescribed for you to use before exercise, unless your physician tells you otherwise. You should always have your inhaled rescue medicine for asthma attacks with you in case you need it.

If your asthma is made worse by acetylsalicylic acid (ASA) (e.g., Aspirin), you should continue to avoid ASA or other non-steroidal anti-inflammatory drugs.

Side Effects

 Any medicine may have unintended or undesirable effects, so-called side effects. SINGULAIR is generally well-tolerated. The most common side effects reported were:
  • abdominal pain

  • headache

  • thirst

  • diarrhea

  • hyperactivity

  • asthma

  • scaly and itchy skin

  • rash.

These were usually mild.

Additionally, the following have been reported:

  • upper respiratory tract infection (common cold)

  • feeling anxious, irritability, disturbance in attention

  • memory impairment, restlessness, sleep walking

  • sleep disorders including dream abnormalities and insomnia, uncontrolled muscle movements

  • dizziness, drowsiness, pins and needles/numbness

  • nose bleed

  • joint pain, muscle aches and muscle cramps

  • tender red lumps under the skin, most commonly on your shins

  • weakness/tiredness, fatigue

  • swelling

  • fever

  • bedwetting in children

Tell your physician or pharmacist if you develop any of the above symptoms, any unusual symptom, or if any known symptom continues or worsens.

Interactions with this medication

In general, SINGULAIR does not interfere with other medicines that you may be taking. However, some medicines may affect how SINGULAIR works, or SINGULAIR may affect how your other medicines work. It is important to tell your physician about all drugs that you are using or plan to use, including those obtained without a prescription.

Proper Use of this medication

Usual dose:

Asthma (for adults, adolescents and children 2 to 14 years old):

Take SINGULAIR once a day in the evening with or without food, as your physician has prescribed.

SINGULAIR oral granules for children 2 to 5 years old can be given either:

  • directly in the mouth;
  • OR
  • all contents mixed with a spoonful of cold or room temperature soft food (for example, applesauce), taking care to see that the entire dose is mixed with the food.

Do not open the packet until ready to use.

Be sure the child is given the entire spoonful of the oral granule/food mixture immediately (within 15 minutes). IMPORTANT: Never store any oral granule/food mixture for use at a later time.

SINGULAIR oral granules are not intended to be dissolved in liquid. However, your child may take liquids after swallowing the SINGULAIR oral granules.

Take SINGULAIR daily for as long as your physician prescribes it in order to maintain control of your or your child's asthma. SINGULAIR can treat your or your child's asthma only if you or your child continue to take it.

It is important that you or your child continue taking SINGULAIR daily as prescribed by your physician, even when you or your child has no symptoms or if you or your child has an asthma attack.

If you are taking other medications along with SINGULAIR your physician will instruct you how and when to take each medication. Your physician will increase or decrease the doses of these medications as needed.

Seasonal Allergic Rhinitis (for adults and adolescents 15 years and older):

Take SINGULAIR once a day in the evening with or without food, as your physician has prescribed.

Remember that your physician has prescribed this medicine only for you or your child. Never give it to anyone else.

Follow up with your physician to ensure your continued health and safety.


In case of drug overdose, contact a health care practitioner, hospital emergency department or regional Poison Control Centre immediately, even if there are no symptoms.

Missed dose:

Try to take SINGULAIR as prescribed. However, if you miss a dose, just resume the usual schedule of one tablet or packet once daily.

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The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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