Montelukast

Montelukast is used regularly to prevent wheezing and shortness of breath caused by asthma and decrease the number of asthma attacks. Montelukast is also used before exercise to prevent breathing problems. This medication can help decrease the number of times you need to use your rescue inhaler. This medication is also used to relieve symptoms of hay fever and allergic rhinitis (such as sneezing, stuffy/runny/itchy nose).

This drug works by blocking certain natural substances (leukotrienes) that may cause or worsen asthma and allergies. It helps make breathing easier by reducing swelling (inflammation) in the airways.

• Montelukast is available under the following different brand names: Singulair.

Dosage Forms & Strengths

Tablet

• 10 mg

Tablet, chewable

• 4 mg
• 5 mg

Oral granules

• 4 mg//packet

Dosage Considerations – Should be Given as Follows:

Asthma

• Adult: 10 mg (single 10-mg tablet) orally once daily in the evening
• Children under 12 months: Safety and efficacy not established
• Children 12-24 months: 4 mg (granules) orally once daily in the evening
• Children 2-6 years: 4 mg (chewable tablet or granules) orally once daily in the evening
• Children 6-15 years: 5 mg (chewable tablet) orally once daily in the evening
• Children over 15 years: 10 mg (conventional tablet) orally once daily in the evening

Exercise-Induced Bronchospasm

• 7.5 mg/day orally at bedtime; increase by 7.5-15 mg/day no more frequently than every 1-2 weeks; not to exceed 60 mg/day

Post-traumatic Stress Disorder (Off-label)

Prophylaxis

• Adult: 10 mg orally 2 hours before exercise; do not take additional dose within 24 hours
• Children 6-15 years: 5 mg (chewable tablet) orally 2 hours before exercise; do not take additional dose within 24 hours
• Children over 15 years: 10 mg orally 2 hours before exercise; do not take additional dose within 24 hours
• If taking the drug for another indication, do not take an additional dose to prevent EIB

Allergic or Perennial Rhinitis

• Adult: 10 mg (single 10-mg tablet) orally once daily
• Children under 6 months: Safety and efficacy not established
• Children 6-24 months: 4 mg (granules) orally once daily
• Children 2-6 years: 4 mg (chewable tablet or granules) orally once daily
• Children 6-15 years: 5 mg (chewable tablet) orally once daily
• Children over 15 years: 10 mg (conventional tablet) orally once daily

Seasonal Allergic Rhinitis, Pediatric

• Children under 2 years: Safety and efficacy not established
• Children 2-6 years: 5 mg (chewable tablet) or 4 mg (granules) orally once daily
• Children 6-15 years: 5 mg (chewable tablet) orally once daily
• Children over 15 years: 10 mg (conventional tablet) orally once daily

Administration

• Patients aged 12 years and older with both asthma and allergic rhinitis: 1 dose orally at bedtime
• Patients with allergic rhinitis: Dosing time may be individualized to patient needs
• Granules may be taken directly; mixed in applesauce, carrots, rice, or ice cream; or dissolved in 5 mL of breast milk or baby formula (administer within 15 minutes of opening)

Some adverse drug reactions vary by age group

Common side effects of montelukast include:

• Headache (similar incidence to placebo)
• Abdominal pain
• Eczema
• Influenza
• Laryngitis
• Sore throat
• Viral infection
• Wheezing
• Dental pain
• Dizziness
• Indigestion
• Elevated liver function tests
• Fever
• Gastroenteritis
• Nasal congestion
• Ear infection
• Rash
• Hives
• Bronchitis
• Cough
• Sinus infection (sinusitis)
• Upper respiratory tract infection

Less common side effects of montelukast include:

• Allergic granulomatous angiitis (Churg-Strauss syndrome; rare)
• Cholestatic hepatitis (rare)
• Aggressive behavior, altered behavior, suicidal thoughts

Postmarketing side effects of montelukast reported include:

• Hematologic: Increased bleeding tendency, thrombocytopenia
• Immunologic: Hypersensitivity reactions (e.g., anaphylaxis, hepatic eosinophilic infiltration)
• Psychiatric: Agitation, including aggressive behavior or hostility, anxiousness, depression, disorientation, dream abnormalities, hallucinations, insomnia, irritability, restlessness, sleepwalking, suicidal thinking and behavior (including suicide), tremor
• Neurologic: Drowsiness, numbness and tingling, reduced sense of touch, seizures
• Cardiac: Palpitations
• Respiratory, thoracic, mediastinal: nosebleed, pulmonary eosinophilia
• Gastrointestinal: Diarrhea, indigestion, nausea, pancreatitis, vomiting
• Hepatobiliary: Cases of cholestatic hepatitis, hepatocellular liver injury, and mixed-pattern liver injury have been reported, mostly occurring in combination with other confounding factors (e.g., use of other medications, administration to patients who had the underlying potential for liver disease [e.g., alcohol use or other forms of hepatitis])
• Dermatologic: Skin swelling, bruising, erythema multiforme, erythema nodosum, itching, hives
• Musculoskeletal: Joint pain, muscle pain (including muscle cramps)
• General: Swelling (edema)

This document does not contain all possible side effects and others may occur. Check with your physician for additional information about side effects.

If your doctor has directed you to use this medication, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.

• Severe Interactions of montelukast include:
  • None
• Serious Interactions of montelukast include:
  • idelalisib
  • ivacaftor
• Montelukast has moderate interactions with at least 21 different drugs.
• Montelukast has mild interactions with at least 73 different drugs.

This information does not contain all possible interactions or adverse effects. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share this information with your doctor and pharmacist. Check with your health care professional or doctor for additional medical advice, or if you have health questions, concerns, or for more information about this medicine.

Warnings

• This medication contains montelukast
• Do not take Singulair if you are allergic to montelukast or any ingredients contained in this drug
• Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center immediately

Contraindications

• Hypersensitivity

Effects of Drug Abuse

• No information available

Short-Term Effects

• See "What Are Side Effects Associated with Using Montelukast?"

Long-Term Effects

• See "What Are Side Effects Associated with Using Montelukast?"

Cautions

• Not to be given for acute asthma attacks, including status asthmaticus
• Advise patients to have appropriate rescue medication available
• Inhaled corticosteroid may be reduced gradually; do not abruptly substitute montelukast for inhaled or oral corticosteroids
• Patients with known aspirin sensitivity should continue to avoid aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) while taking montelukast; not to be given for the treatment of bronchoconstriction resulting from aspirin or NSAID intake
• Neuropsychiatric events (e.g., abnormal dreams, agitation) reported
• Systemic eosinophilia was reported, sometimes presenting with clinical features of vasculitis consistent with Churg-Strauss syndrome; these events are usually (but not always) associated with tapering of PO corticosteroid therapy
• Use with caution in phenylketonuria; 4-mg and 5-mg chewable tablets contain phenylalanine

Pregnancy and Lactation

• Montelukast may be acceptable for use during pregnancy. Either animal studies show no risk but human studies are not available, or animal studies showed minor risks, and human studies were done and showed no risk
• It is unknown whether montelukast is excreted in breast milk; use with caution if breastfeeding