Asthma is a long-term inflammatory disease of the airways of the lungs. It is characterized by variable and recurring symptoms, reversible airflow obstruction, and easily triggered bronchospasms. Symptoms include episodes of wheezing, coughing, chest tightness, and shortness of breath. These may occur a few times a day or a few times per week. Depending on the person, asthma symptoms may become worse at night or with exercise.
Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are involved in a wide range of physiological processes, including stress response, immune response, and regulation of inflammation, carbohydrate metabolism, protein catabolism, blood electrolyte levels, and behavior.
A bronchodilator or broncholytic is a substance that dilates the bronchi and bronchioles, decreasing resistance in the respiratory airway and increasing airflow to the lungs. Bronchodilators may be originating naturally within the body, or they may be medications administered for the treatment of breathing difficulties, usually in the form of inhalers. They are most useful in obstructive lung diseases, of which asthma and chronic obstructive pulmonary disease are the most common conditions. Although this remains somewhat controversial, they might be useful in bronchiolitis and bronchiectasis. They are often prescribed but of unproven significance in restrictive lung diseases.
Fluticasone/salmeterol, sold under the brand name Advair among others, is a fixed-dose combination medication containing fluticasone propionate and salmeterol. It is used in the management of asthma and chronic obstructive pulmonary disease (COPD). It is used by inhaling the medication into the lungs.
Zafirlukast is an orally administered leukotriene receptor antagonist (LTRA) used for the chronic treatment of asthma. While zafirlukast is generally well tolerated, headache and stomach upset often occur. Some rare side effects can occur, which can be life-threatening, such as liver failure. Churg-Strauss syndrome has been associated with zafirlukast, but the relationship isn't thought to be causative in nature. Overdoses of zafirlukast tend to be self-limiting.
Budesonide/formoterol, sold under the brand name Symbicort among others, is a fixed-dose combination medication used in the management of asthma or chronic obstructive pulmonary disease (COPD). It contains budesonide, a steroid and formoterol, a long-acting β2-agonist (LABA). The product monograph does not support its use for sudden worsening or treatment of active bronchospasm. However, a 2020 review of the literature does support such use. It is used by breathing in the medication.
Formoterol, also known as eformoterol, is a long-acting β2 agonist (LABA) used as a bronchodilator in the management of asthma and chronic obstructive pulmonary disease (COPD). Formoterol has an extended duration of action compared to short-acting β2 agonists such as salbutamol (albuterol), which are effective for 4 h to 6 h. Formoterol has a relatively rapid onset of action compared to other LABAs, and is effective within 2-3 minutes. The 2022 Global Initiative for Asthma report recommends a combination formoterol/inhaled corticosteroid inhaler as both a preventer and reliever treatment for asthma in adults. In children, a short-actingβ2 agonist is still recommended.
Beta2-adrenergic agonists, also known as adrenergic β2 receptor agonists, are a class of drugs that act on the β2 adrenergic receptor. Like other β adrenergic agonists, they cause smooth muscle relaxation. β2 adrenergic agonists' effects on smooth muscle cause dilation of bronchial passages, vasodilation in muscle and liver, relaxation of uterine muscle, and release of insulin. They are primarily used to treat asthma and other pulmonary disorders. Bronchodilators are considered an important treatment regime for Chronic obstructive pulmonary disease (COPD) and are usually used in combination with short acting medications and long acting medications in a combined inhaler.
Bronchoconstriction is the constriction of the airways in the lungs due to the tightening of surrounding smooth muscle, with consequent coughing, wheezing, and shortness of breath.
Long-acting β adrenoceptor agonists are usually prescribed for moderate-to-severe persistent asthma patients or patients with chronic obstructive pulmonary disease (COPD). They are designed to reduce the need for shorter-acting β2 agonists such as salbutamol (albuterol), as they have a duration of action of approximately 12 hours in comparison with the 4-to-6-hour duration of salbutamol, making them candidates for sparing high doses of corticosteroids or treating nocturnal asthma and providing symptomatic improvement in patients with COPD. With the exception of formoterol, long-acting β2 agonists are not recommended for the treatment of acute asthma exacerbations because of their slower onset of action compared to salbutamol. Their long duration of action is due to the addition of a long, lipophilic side-chain that binds to an exosite on adrenergic receptors. This allows the active portion of the molecule to continuously bind and unbind at β2 receptors in the smooth muscle in the lungs.
Exercise-induced bronchoconstriction (EIB) occurs when the airways narrow as a result of exercise. This condition has been referred to as exercise-induced asthma (EIA), however this term is no longer preferred. While exercise does not cause asthma, it is frequently an asthma trigger.
Fenoterol is a β adrenoreceptor agonist. It is classed as sympathomimetic β2 agonist and an inhaled bronchodilator asthma medication.
Occupational asthma is new onset asthma or the recurrence of previously quiescent asthma directly caused by exposure to an agent at workplace. It is an occupational lung disease and a type of work-related asthma. Agents that can induce occupational asthma can be grouped into sensitizers and irritants.
Obstructive lung disease is a category of respiratory disease characterized by airway obstruction. Many obstructive diseases of the lung result from narrowing (obstruction) of the smaller bronchi and larger bronchioles, often because of excessive contraction of the smooth muscle itself. It is generally characterized by inflamed and easily collapsible airways, obstruction to airflow, problems exhaling, and frequent medical clinic visits and hospitalizations. Types of obstructive lung disease include; asthma, bronchiectasis, bronchitis and chronic obstructive pulmonary disease (COPD). Although COPD shares similar characteristics with all other obstructive lung diseases, such as the signs of coughing and wheezing, they are distinct conditions in terms of disease onset, frequency of symptoms, and reversibility of airway obstruction. Cystic fibrosis is also sometimes included in obstructive pulmonary disease.
Asthma is a common pulmonary condition defined by chronic inflammation of respiratory tubes, tightening of respiratory smooth muscle, and episodes of bronchoconstriction. The Centers for Disease Control and Prevention estimate that 1 in 11 children and 1 in 12 adults have asthma in the United States of America. According to the World Health Organization, asthma affects 235 million people worldwide. There are two major categories of asthma: allergic and non-allergic. The focus of this article will be allergic asthma. In both cases, bronchoconstriction is prominent.
Chronic obstructive pulmonary disease (COPD) is a type of progressive lung disease characterized by long-term respiratory symptoms and airflow limitation. The main symptoms of COPD include shortness of breath and a cough, which may or may not produce mucus. COPD progressively worsens, with everyday activities such as walking or dressing becoming difficult. While COPD is incurable, it is preventable and treatable. The two most common types of COPD are emphysema and chronic bronchitis and have been the two classic COPD phenotypes. However, this basic dogma has been challenged as varying degrees of co-existing emphysema, chronic bronchitis, and potentially significant vascular diseases have all been acknowledged in those with COPD, giving rise to the classification of other phenotypes or subtypes. Emphysema is defined as enlarged airspaces (alveoli) whose walls have broken down resulting in permanent damage to the lung tissue. Chronic bronchitis is defined as a productive cough that is present for at least three months each year for two years. Both of these conditions can exist without airflow limitation when they are not classed as COPD. Emphysema is just one of the structural abnormalities that can limit airflow and can exist without airflow limitation in a significant number of people. Chronic bronchitis does not always result in airflow limitation but in young adults with chronic bronchitis who smoke, the risk of developing COPD is high. Many definitions of COPD in the past included emphysema and chronic bronchitis, but these have never been included in GOLD report definitions. Emphysema and chronic bronchitis remain the predominant phenotypes of COPD but there is often overlap between them and a number of other phenotypes have also been described. COPD and asthma may coexist and converge in some individuals. COPD is associated with low-grade systemic inflammation.
β2-adrenoceptor agonists are a group of drugs that act selectively on β2-receptors in the lungs causing bronchodilation. β2-agonists are used to treat asthma and COPD, diseases that cause obstruction in the airways. Prior to their discovery, the non-selective beta-agonist isoprenaline was used. The aim of the drug development through the years has been to minimise side effects, achieve selectivity and longer duration of action. The mechanism of action is well understood and has facilitated the development. The structure of the binding site and the nature of the binding is also well known, as is the structure activity relationship.
Fluticasone furoate/umeclidinium bromide/vilanterol, sold under the brand name Trelegy Ellipta among others, is a fixed-dose combination inhaled medication that is used for the maintenance treatment of chronic obstructive pulmonary disease (COPD). The medications work in different ways: fluticasone furoate is an inhaled corticosteroid (ICS), umeclidinium is a long-acting muscarinic antagonist (LAMA), and vilanterol is a long-acting beta-agonist (LABA).
Asthma triggers are factors or stimuli that provoke the exacerbation of asthma symptoms or increase the degree of airflow disruption, which can lead to an asthma attack. An asthma attack is characterized by an obstruction of the airway, hypersecretion of mucus and bronchoconstriction due to the contraction of smooth muscles around the respiratory tract. Its symptoms include a wide range of manifestations such as breathlessness, coughing, a tight chest and wheezing.
Asthma phenotyping and endotyping is a novel approach to asthma classification inspired by precision medicine. It seeks to separate the clinical presentations or clusters of signs and symptoms of asthma, known as asthma phenotypes, from their underlying etiologies or causes, known as asthma endotypes.
