Patients with bronchospasm, including those with asthma or COPD, are treated with metaproterenol (Alupent), an oral beta-2 receptor agonist.

Metaproterenol Uses:

• Asthma/ Bronchospasm:

  • It is used in the treatment of patients with bronchial asthma and for bronchospasm that occurs in association with acute or chronic bronchitis or emphysema.

Metaproterenol (Alupent) Dose in Adults:

Metaproterenol (Alupent) Dose in the treatment of Asthma/ Bronchospasm:

• Oral: 20 mg 3 or 4 times a day

Note: Oral bronchodilators are not advised for routine usage in the management of acute asthma or long-term daily maintenance treatment due to the sluggish onset of action and significant risk of adverse events compared to inhalational medications.

Metaproterenol (Alupent) Dose in Children:

Note: Oral bronchodilators are not advised for routine usage in the management of acute asthma or long-term daily maintenance treatment due to the sluggish onset of action and significant risk of adverse events compared to inhalational medications.

Metaproterenol (Alupent) dose in Asthma/ bronchospasm:

• Children and Adolescents:

  • Children ≤5 years:
    • Oral: 3 or 4 split doses of 1.3 to 2.6 mg/kg/day, given every 6 to 8 hours; the maximum dose is 10 mg/dose.
  • Children 6 to 9 years or weighing <27 kg:
    • Oral: Orally, three or four times a day, 10 mg.
  • Children >9 years and Adolescents or weighing ≥27 kg:
    • Oral: 3 to 4 times a day, 20 mg.

Pregnancy Risk Factor C

• Animal reproduction studies have shown adverse pregnancy outcomes. 
• Beta receptor agonists can reduce uterine contractility, and may cause maternal and fetal tachycardia.
• To avoid adverse pregnancy outcomes like preterm birth, low neonatal weight, pre-eclampsia and an increased risk of perinatal death, maternal asthma must be managed well.
• Oral treatment with beta-receptor-agonists is not recommended during pregnancy.

Use during breastfeeding:

• It is unknown whether the drug will be excreted into breastmilk. 
• Although the manufacturer suggests that you avoid it while breastfeeding, beta-receptor agonists should not be considered contraindicated during lactation.

Dose in Kidney Disease:

There are no dosage adjustments provided in the manufacturer's labeling.

Dose in Liver disease:

There are no dosage adjustments provided in the manufacturer's labeling.

Common Side Effects of Metaproterenol (Alupent):

• Cardiovascular:

  • Tachycardia

• Central nervous system:

  • Nervousness

• Neuromuscular & skeletal:

  • Tremor

Less Common Side Effects of Metaproterenol (Alupent):

• Cardiovascular:

  • Palpitations

• Central nervous system:

  • Headache
  • Dizziness
  • Insomnia
  • Fatigue

• Gastrointestinal:

  • Nausea
  • Diarrhea

• Respiratory:

  • Exacerbation of asthma

Contraindications to Metaproterenol (Alupent):

• Allergy to metaproterenol and any component of this formulation
• Pre-existing cardiac tachyarrhythmias.

Warnings and precautions

• Hypersensitivity reactions

  • The treatment has been associated with immediate hypersensitivity reactions such as urticaria and angioedema, rash, and/or bronchospasm. 
  • Patients who have had an allergic reaction should not use the drug.

• Asthma

  • Patients with Asthma or other conditions of bronchial hyperreactivity should prefer inhalational treatment. 
  • Metaproterenol, a beta-2 agonist that is less selective, is more likely to cause cardiac stimulation.
  • Patients with heart disease and at risk for developing it should avoid oral medications.

• Cardiovascular disease

  • Blood pressure, heart rate, and CNS excitement can all rise as a result of non-selective beta receptor activation.
  • This medication should not be used by people with cardiovascular illness (hypertension or heart failure).

• Chronic obstructive lung disease (COPD):

  • Patients with COPD or other conditions of bronchial hyperreactivity should prefer inhalational treatment. 
  • Patients with heart disease, or at high risk for developing it, should avoid oral medications.

• Diabetes:

  • Patients with diabetes and prediabetes should be cautious about activating beta-receptors.

• Glaucoma:

  • Glaucoma patients should not use it as it can cause an increase in intraocular pressure.

• Hyperthyroidism:

  • Thyroid activity is stimulated by activation of beta-receptors. 
  • Patients with hyperthyroidism and other thyroid diseases should use it cautiously.

• Hypokalemia

  • The activation of beta-2 receptors decreases serum potassium by causing it to move from extracellular fluid to cells. 
  • Patients with hypokalemia and those at high risk should not use it.

• Seizures:

  • The stimulation of the central nervous system by beta-receptors may lower the seizure threshold.
  • It should not be used by patients who are at high risk of suffering seizures.

Metaproterenol (orciprenaline): Drug Interaction

Monitoring parameters:

• Heart rate
• Blood pressure
• FEV-1
• Peak flow
• Pulmonary function tests
• Monitor the patient for CNS stimulation
• Monitor plasma glucose in patients with pre-diabetes or diabetes
• serum potassium

How to administer Metaproterenol (Alupent)?

It may be administered without regard to meals. However, if the patient experiences a gastrointestinal upset, it may be administered with meals.

Mechanism of action of Metaproterenol (Alupent):

• It stimulates beta-2-receptors in the respiratory tract (airways). 
• Adenosine Triphosphate (ATP) is converted by beta-2 receptor stimulation into 3'-5'cyclic adenosine Monophosphate (3'-5'cyclic adenosine (cAMP) in the smooth muscles of your airway.
• This causes bronchial relaxation.

The onset of action:

• When administered orally, bronchodilation occurs in about 30 minutes.

Peak effect:

• The peak effect after oral administration is seen in about one hour.

Duration:

• Its duration of action ranges from 2 to 6 hours, depending on how it is administered.

Absorption:

• It is well absorbed from the GI tract when taken orally.

Metabolism:

• It undergoes extensive first-pass metabolism in the liver. Only about 40% of the oral dose of the drug is available systemically.

Excretion:

• It is excreted mainly as glucuronic acid conjugates

International Brand Names of Metaproterenol:

• Alupent
• Astmopent
• Dianben
• Fromin
• Glumin XR
• Metfil
• Nonasma
• Obid

Metaproterenol Brand Names in Pakistan:

No Brands Available in Pakistan.