What is this medicine?

MONTELUKAST (mon te LOO kast) is used to prevent and treat the symptoms of asthma. It is also used to treat allergies. Do not use for an acute asthma attack.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): Singulair

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:

  • liver disease
  • an unusual or allergic reaction to montelukast, other medicines, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

This medicine should be given by mouth. Follow the directions on the prescription label. Take this medicine at the same time every day. You may take this medicine with or without meals. Do not chew the tablets. Do not stop taking your medicine unless your doctor tells you to.

Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed. While this drug may be prescribed for children as young as 15 years of age for selected conditions, precautions do apply.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, skip it. Take your next dose at the normal time. Do not take extra or 2 doses at the same time to make up for the missed dose.

What may interact with this medicine?

  • anti-infectives like rifampin and rifabutin
  • medicines for seizures like phenytoin, phenobarbital, and carbamazepine

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medicine?

Visit your doctor or health care professional for regular checks on your progress. Tell your doctor or health care professional if your allergy or asthma symptoms do not improve. Take your medicine even when you do not have symptoms. Do not stop taking any of your medicine(s) unless your doctor tells you to.

If you have asthma, talk to your doctor about what to do in an acute asthma attack. Always have your inhaled rescue medicine for asthma attacks with you.

Patients and their families should watch for new or worsening thoughts of suicide or depression. Also watch for sudden changes in feelings such as feeling anxious, agitated, panicky, irritable, hostile, aggressive, impulsive, severely restless, overly excited and hyperactive, or not being able to sleep. Any worsening of mood or thoughts of suicide or dying should be reported to your health care professional right away.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:

  • allergic reactions like skin rash or hives, or swelling of the face, lips, or tongue
  • breathing problems
  • changes in emotions or moods
  • confusion
  • depressed mood
  • fever or infection
  • hallucinations
  • joint pain
  • painful lumps under the skin
  • pain, tingling, numbness in the hands or feet
  • redness, blistering, peeling, or loosening of the skin, including inside the mouth
  • restlessness
  • seizures
  • sleep walking
  • signs and symptoms of infection like fever; chills; cough; sore throat; flu-like illness
  • signs and symptoms of liver injury like dark yellow or brown urine; general ill feeling or flu-like symptoms; light-colored stools; loss of appetite; nausea; right upper belly pain; unusually weak or tired; yellowing of the eyes or skin
  • sinus pain or swelling
  • stuttering
  • suicidal thoughts or other mood changes
  • tremors
  • trouble sleeping
  • uncontrolled muscle movements
  • unusual bleeding or bruising
  • vivid or bad dreams

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • dizziness
  • drowsiness
  • headache
  • runny nose
  • stomach upset
  • tiredness

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medicine?

Keep out of the reach of children.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Protect from light and moisture. Keep this medicine in the original bottle. Throw away any unused medicine after the expiration date.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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