formoterol

Action and Spectrum

Action: 

Formoterol is a long-acting beta-2 adrenergic agonist (LABA) that works by selectively stimulating beta-2 receptors in the bronchial smooth muscle. This leads to relaxation of the airway muscles, resulting in bronchodilation and improved airflow.

Spectrum: 

Formoterol is used in the maintenance treatment of chronic respiratory diseases that involve reversible or partially reversible airway obstruction. Its primary indications include asthma, but only when used in combination with inhaled corticosteroids to ensure safety and effectiveness. It is also commonly prescribed for chronic obstructive pulmonary disease (COPD), including chronic bronchitis and emphysema, to improve airflow and reduce symptoms. 

Drug Interaction

Adverse Reaction

Frequency defined:  

1%-10%  

Chest pain (2%) 

Anxiety (2%) 

Headache 

Voice disorder 

Diarrhea 

Pruritis 

Skin rash 

Muscle cramps 

Tremor 

Abdominal pain 

Vomiting 

Nausea 

Fever   

<1%: 

Angina pectoris  

Cardiac arrhythmia 

Cough 

Dermatitis 

Fatigue 

Variable blood pressure 

Restlessness 

Nervousness  

Black Box Warning

None

Contraindication / Caution

Contraindication: 

Hypersensitivity 

Caution: 

Arrhythmias 

Hypertension 

Ischemic heart disease 

Seizure disorders 

Thyrotoxicosis 

Diabetes mellitus 

Pregnancy / Lactation

Pregnancy consideration: No adverse effects have been reported in the maternal use of beta-2 agonists. formoterol can be used for the management of asthma in pregnant women. 

Lactation: Excretion of formoterol in breast milk is not known.  

Pregnancy category: 

• Category A: Satisfactory and well-controlled studies show no risk to the fetus in the first or later trimester. 
• Category B: There is no evidence of risk to the fetus found in animal reproduction studies and there are not enough studies on pregnant women. 
• Category C: Adverse effects on the fetus found with evidence in animal reproduction studies and no adequate evidence for an effect in humans, care must be taken for potential risks in pregnant women 
• Category D: There is adequate data available with sufficient evidence of human fetal risk from various platforms, but despite potential risks may be used only in emergency cases for potential benefits. 
• Category X: Drugs listed in this category outweigh risks over benefits These category drugs should be prohibited for pregnant women. 
• Category N: There is no data available for the drug under this category. 

Pharmacology

Formoterol is a long-acting beta-2 adrenergic agonist (LABA) that provides prolonged bronchodilation by selectively stimulating beta-2 receptors in bronchial smooth muscle. This stimulation activates adenylate cyclase, leading to an increase in cyclic AMP (cAMP) levels, which relaxes airway muscles and helps improve airflow in obstructive airway conditions. 

Pharmacokinetics: 

Absorption 

Formoterol reaches peak plasma concentration of approximately 92 pg/mL within about 5 minutes after administration. 

Distribution 

It is moderately bound to plasma proteins, with a binding rate of 61–64%. 

Metabolism 

The drug is primarily metabolized in the liver by cytochrome P450 enzymes, including CYP2D6, CYP2C19, CYP2C9, and CYP2A6. 

Excretion and Elimination 

Formoterol has a half-life of around 10 hours and a clearance rate of approximately 150 mL/min. It is eliminated from the body through both the urine (66%) and feces (33%). 

Adminstartion

Formoterol is administered via inhalation, using either a dry powder inhaler (DPI) or metered-dose inhaler (MDI), depending on the formulation. The patient should inhale the dose deeply through the mouth, ensuring proper technique to maximize delivery to the lungs. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: formoterol 

Pronounced: for-mat-e-rol 

Why do we use formoterol? 

Formoterol is a long-acting beta-2 adrenergic agonist (LABA) used for the maintenance treatment of respiratory conditions involving airway obstruction. It is commonly prescribed for asthma, but always in combination with an inhaled corticosteroid to reduce the risk of severe exacerbations. Formoterol is also indicated for the management of chronic obstructive pulmonary disease (COPD), including chronic bronchitis and emphysema, where it helps improve airflow and reduce symptoms such as wheezing and breathlessness. In some cases, it may be used to prevent exercise-induced bronchospasm when part of a broader controller regimen. It provides bronchodilation for up to 12 hours and is not suitable for the treatment of acute asthma symptoms or sudden breathing difficulties.