Singulair (Montelukast)

Composition

One coated tablet contains:
Montelukast 4/5/10 mg.

Pharmacological action

Singular is a leukotriene receptor antagonist.
Montelukast inhibits cysteinyl leukotriene receptors of the airway epithelium, showing simultaneously the ability to inhibit bronchospasm caused by inhalation of cysteinyl leukotriene LTD4 in patients with bronchial asthma.
A dose of 5 mg is sufficient to stop LTD4-induced bronchospasm. The use of montelukast in doses exceeding 10 mg/day once/day does not increase the effectiveness of the drug. Montelukast causes bronchodilatation within 2 hours after oral administration and may complement bronchodilatation induced by beta2-adrenomimetics.

Indications

Prophylaxis and long-term treatment of bronchial asthma in adults and children aged 6 years and older, including: prevention of daytime and nighttime symptoms of the disease; treatment of bronchial asthma in patients with hypersensitivity to acetylsalicylic acid prevention of exercise-induced bronchospasm.
Cure of daytime and nighttime symptoms: seasonal allergic rhinitis in adults and children aged 6 years and older; persistent allergic rhinitis in adults and children aged 6 years and older.

Use during pregnancy and lactation

Singulair should be used during pregnancy and lactation only in cases when the expected benefit to the mother exceeds the potential risk to the fetus or child.

Contraindications

Hypersensitivity to the components of the drug.
With caution: pregnancy, lactation.

Side effects

  • Allergic reactions: anaphylaxis, angioneurotic edema, rash, pruritus, urticaria, very rare – eosinophilic liver infiltration.
  • CNS disorders: unusual vivid dreams, hallucinations, somnolence, irritability, agitation (including aggressive behavior), fatigue, headache, suicidal thoughts and suicidal behavior (suicidality), insomnia, paresthesia/hypoesthesia; very rare – seizures.
  • Digestive system: nausea, vomiting, diarrhea, abdominal pain.
  • Musculoskeletal system: arthralgia, myalgia, including muscle cramps.
  • Dermatological reactions: erythema nodosum, tendency to formation of subcutaneous hemorrhages.
  • Other: tendency to increased bleeding, subcutaneous hemorrhages, palpitations, edema.

In general, Singulair is well tolerated. Side effects are usually mild and usually do not require treatment withdrawal. The overall incidence of side effects reported with Singulair is comparable with that for placebo.

Interactions

Singulair may be administered together with other medications commonly used for the prevention and long-term treatment of bronchial asthma and/or treatment of allergic rhinitis.
The recommended therapeutic dose of montelukast had no clinically significant effect on the pharmacokinetics of the following drugs: theophylline, prednisone, prednisolone, oral contraceptives, terfenadine, digoxin and warfarin.
AUC value of montelukast is decreased concomitant administration of phenobarbital by approximately 40%, which does not require changes in dosing regimen of Singulair.
In vitro studies have found that montelukast inhibits the cytochrome CYP2C8 isoenzyme system. However, in an in vivo interdrug interaction study of montelukast and rosiglitazone (metabolized with participation of the cytochrome system CYP 2C8 isoenzyme), there was no evidence that montelukast inhibits the CYP 2C8 isoenzyme. Thus, in clinical practice the effect of montelukast on CYP 2C8-mediated metabolism of several drugs, including paclitaxel, rosiglitazone, repaglinide and others is not expected.
Combined treatment with bronchodilators: Singulair is a reasonable adjunct to monotherapy with bronchodilators if the latter do not adequately control bronchial asthma. Once a therapeutic effect has been achieved (usually after the first dose) from treatment with Singulair, a gradual reduction in the dose of bronchodilators can begin.
Combined treatment with inhaled glucocorticosteroids: Treatment with Singulair provides additional therapeutic effect in patients using inhaled glucocorticosteroids. Once stabilization has been achieved, a reduction in the dose of the corticosteroid can be initiated – gradually and under medical supervision. Complete withdrawal of inhaled glucocorticosteroids is sometimes acceptable, but abrupt replacement of inhaled corticosteroids with Singulair is not recommended.

How to take Singulair, course of treatment and dosage

The drug is taken orally once a day regardless of meals.
In bronchial asthma: 1 tablet at night.
With bronchial asthma and allergic rhinitis: 1 tablet at night.
In allergic rhinitis: 1 tablet a day on an individual basis, depending on the time of the greatest exacerbation of symptoms.
The therapeutic effect of Singular on the indicators reflecting the course of bronchial asthma develops during the first day. The patient should continue to take Singulair both during the period of achieving control of bronchial asthma symptoms and during exacerbation of the disease. Singulair may be added to treatment with bronchodilators and inhaled GCS.
The therapeutic effect of Singulair on indicators reflecting the severity of the course of bronchial asthma develops within one day. The patient should continue taking Singulair both during the period of achieving control of bronchial asthma symptoms and during exacerbation of the disease.
For elderly patients, patients with renal insufficiency, patients with mild or moderate hepatic dysfunction, as well as depending on gender, no special dose adjustment is required.

Overdose

Symptoms: symptoms of overdose of Singulair in patients with chronic bronchial asthma when administered at a dose greater than 200 mg/day for 22 weeks and at a dose of 900 mg/day for 1 week have not been identified.
There are reports of acute overdose of montelukast in children (at a dose of at least 150 mg/day). Clinical and laboratory data suggest that the safety profile of Singulair in children corresponds to the safety profile in adults and elderly patients. The most frequent adverse events were feelings of thirst, somnolence, mydriasis, hyperkinesias and abdominal pain.
Treatment: administration of symptomatic therapy.
There are no data on possibility of montelukast excretion by peritoneal dialysis or hemodialysis.

Special indications

Singular is not recommended for treatment of acute attacks of bronchial asthma. In acute bronchial asthma patients should be prescribed drugs for curative and preventive therapy.
It is recommended that patients with bronchial asthma always carry emergency medications (short-acting inhaled beta-agonists).
To relieve an acute attack of bronchial asthma after physical activity, a drug to relieve the attack is used, i.e., a short-acting inhaled beta-agonist.
Treatment with Singulair does not guarantee absolute prevention of exacerbations.
During asthma exacerbations and the need to use emergency drugs (short-acting inhaled beta-agonists) to control attacks, Singulair should not be discontinued.
Patients with proven allergy to acetylsalicylic acid and other non-steroidal anti-inflammatory drugs should avoid contact with these drugs during treatment with Singulair, because Singulair, while improving respiratory function in patients with allergic bronchial asthma, does not prevent bronchoconstriction caused by NSAIDs.
The dose of inhaled glucocorticosteroids used concomitantly with Singulair is reduced gradually under medical supervision. Abrupt replacement of inhaled or oral glucocorticosteroids with Singulair is unacceptable.
In rare cases, reduction of the dose of systemic glucocorticosteroids in patients receiving concomitant anti-asthmatic drugs, including leukotriene receptor blockers, has been accompanied by one or more of the following complications: eosinophilia, hemorrhagic rash, worsening of pulmonary symptoms, cardiac complications and/or neuropathy, sometimes diagnosed as Churg-Strauss syndrome (systemic eosinophilic vasculitis). Although a causal relationship between these side effects and treatment with leukotriene receptor antagonists has not been established, caution should be exercised when reducing the dose of systemic glucocorticosteroids during treatment with Singulair and appropriate patient monitoring should be ensured.
Patients with phenylketonuria should be informed that Singulair contains 1.2 mg of aspartame in one chewable tablet.
No age differences in the profile of efficacy and safety of Singular have been found.
Effect on the ability to drive vehicles and operate mechanisms:
No evidence has been found that taking Singulair affects the ability to drive or operate moving mechanisms.