Respiratory System Drugs — MCQs

Respiratory System Drugs Indian Medical PG Practice Questions and MCQs

Question 261: Which of the following drugs is contraindicated in patients with asthma due to its potential to cause bronchoconstriction?

A. Lisinopril (ACE inhibitor)
B. Atorvastatin (statin)
C. Amlodipine (calcium channel blocker)
D. Propranolol (non-selective beta-blocker) (Correct Answer)

Explanation: ***Propranolol (non-selective beta-blocker)*** - **Non-selective beta-blockers** block both **beta-1 and beta-2 receptors** - Blockade of **beta-2 receptors** in bronchial smooth muscle leads to **bronchoconstriction** in susceptible individuals like asthmatics - This effect can trigger or worsen asthma symptoms, making it an **absolute contraindication** in patients with asthma - Cardioselective beta-blockers (like atenolol) are relatively safer but still used with caution *Lisinopril (ACE inhibitor)* - ACE inhibitors can cause a **dry cough** due to accumulation of bradykinin, not bronchoconstriction - The cough is due to bradykinin and substance P accumulation, not bronchospasm - Generally **safe in asthma** patients - Angioedema is a rare but serious side effect, unrelated to bronchial effects *Atorvastatin (statin)* - **Statins** (HMG-CoA reductase inhibitors) are used to lower cholesterol - No direct effects on **bronchial tone** or respiratory function - **Safe for use** in patients with asthma - No contraindications related to respiratory disease *Amlodipine (calcium channel blocker)* - **Dihydropyridine calcium channel blockers** cause vascular smooth muscle relaxation - Do **not cause bronchoconstriction** and are safe in asthma patients - May have mild **bronchodilatory effects** due to smooth muscle relaxation - No respiratory contraindications

Question 262: In the management of asthma, which drug class is the most effective for long-term control and prevention of symptoms?

A. Beta-agonists
B. Corticosteroids (Correct Answer)
C. Leukotriene modifiers
D. Anticholinergics

Explanation: **Corticosteroids** (Correct Answer) - **Inhaled corticosteroids** are the most effective anti-inflammatory medications for long-term control of persistent asthma, reducing airway hyperresponsiveness and preventing exacerbations. - They work by suppressing the inflammatory response in the airways, leading to decreased mucus production and swelling. - Inhaled corticosteroids are the **cornerstone of asthma management** as per GINA (Global Initiative for Asthma) guidelines. *Beta-agonists* (Incorrect) - **Short-acting beta-agonists (SABAs)** are primarily used as **rescue medications** for acute symptom relief, as they rapidly relax airway smooth muscle. - **Long-acting beta-agonists (LABAs)** are used for long-term control but generally in combination with inhaled corticosteroids, not as monotherapy, due to their limited anti-inflammatory action. - LABAs alone do not address the underlying inflammation in asthma. *Leukotriene modifiers* (Incorrect) - These drugs, such as montelukast, block the action of **leukotrienes**, which are inflammatory mediators. - While effective for some patients, they are generally **less potent than inhaled corticosteroids** for overall asthma control and are often used as **add-on therapy** or alternative for mild asthma. - They may be particularly useful in aspirin-sensitive asthma and exercise-induced bronchoconstriction. *Anticholinergics* (Incorrect) - **Short-acting anticholinergics** (e.g., ipratropium) are used as **bronchodilators** and can be helpful in acute asthma exacerbations or for patients who cannot tolerate beta-agonists. - **Long-acting anticholinergics** are primarily used in **COPD management** rather than as first-line asthma therapy. - Their role in asthma is limited compared to corticosteroids, which address the underlying inflammatory pathophysiology.

Question 263: Which of the following is a leukotriene receptor antagonist used in the management of asthma?

A. Montelukast (Correct Answer)
B. Albuterol
C. Fluticasone
D. Salmeterol

Explanation: ***Correct Answer: Montelukast*** - **Montelukast** is a selective and orally active **leukotriene receptor antagonist** that specifically blocks the cysteinyl leukotriene 1 (CysLT1) receptor. - By blocking leukotrienes, it helps to **reduce inflammation**, bronchoconstriction, and mucus secretion, thus preventing asthma symptoms. - It is particularly useful for **exercise-induced asthma** and as an add-on therapy to inhaled corticosteroids. *Incorrect: Albuterol* - **Albuterol** is a **short-acting beta-2 adrenergic agonist (SABA)**, primarily used as a **rescue inhaler** for acute asthma symptoms. - It works by **relaxing the smooth muscles** in the airways, leading to bronchodilation, but does not target leukotrienes. *Incorrect: Fluticasone* - **Fluticasone** is an **inhaled corticosteroid (ICS)**, a cornerstone of long-term asthma control. - It reduces airway inflammation by **suppressing the immune response** at a cellular level, rather than blocking leukotriene receptors. *Incorrect: Salmeterol* - **Salmeterol** is a **long-acting beta-2 adrenergic agonist (LABA)**, used for long-term asthma control in combination with an inhaled corticosteroid. - It provides prolonged bronchodilation by **stimulating beta-2 receptors**, but does not act on leukotriene pathways.

Question 264: Which bronchodilator drug is considered the first-line therapy for acute asthma attacks due to its rapid onset of action?

A. Salmeterol
B. Ipratropium
C. Salbutamol (Correct Answer)
D. Tiotropium

Explanation: ***Salbutamol*** - **Salbutamol** is a **short-acting beta-2 agonist (SABA)**, which means it rapidly relaxes the smooth muscles of the airways [1], [4]. - Its **quick onset of action** (within minutes) makes it the preferred drug for immediate relief of **acute asthma symptoms** like shortness of breath and wheezing [1], [3]. *Salmeterol* - **Salmeterol** is a **long-acting beta-2 agonist (LABA)**, providing bronchodilation for up to 12 hours [5]. - It is used for **maintenance therapy** to prevent asthma attacks, not for acute relief, and should always be used in combination with an inhaled corticosteroid. *Ipratropium* - **Ipratropium** is a **short-acting anticholinergic** that blocks muscarinic receptors in the airways, leading to bronchodilation [2]. - While it can be used as an **adjunct to SABAs** in severe acute asthma, it has a slower onset of action and is not considered first-line monotherapy for acute attacks. *Tiotropium* - **Tiotropium** is a **long-acting anticholinergic** primarily used for the maintenance treatment of **COPD** and sometimes as an add-on therapy for severe asthma [5]. - Its **slow onset** and prolonged action make it unsuitable for the immediate relief of acute asthma symptoms.

Question 265: In assessing treatment options for a patient with severe asthma, what would be the most immediate action to alleviate symptoms?

A. Long-term corticosteroid therapy
B. Short-acting beta-agonist inhaler use (Correct Answer)
C. Introduction of leukotriene modifiers
D. Gradual increase in physical activity

Explanation: ***Short-acting beta-agonist inhaler use*** - **Short-acting beta-agonists (SABAs)** provide rapid relief of acute asthma symptoms by **bronchodilation**, making them the most immediate and effective action for symptom alleviation [1]. - They work by relaxing the **smooth muscles of the airways**, opening them up and easing breathing during an asthma attack. *Long-term corticosteroid therapy* - **Long-term corticosteroid therapy** is a cornerstone of **asthma control and prevention of exacerbations**, but it does not provide immediate relief for acute symptoms [2]. - Its effects on reducing airway inflammation and hyper-responsiveness take days to weeks to become apparent. *Introduction of leukotriene modifiers* - **Leukotriene modifiers** help in long-term asthma control by blocking specific inflammatory pathways, but they do not offer immediate relief during acute exacerbations [1]. - Their primary role is to reduce inflammation and prevent symptoms over time, typically acting over several days to weeks. *Gradual increase in physical activity* - A **gradual increase in physical activity** can improve overall lung function and cardiovascular health in patients with stable asthma, but it is not an immediate treatment for symptom alleviation. - In fact, vigorous physical activity can sometimes trigger asthma symptoms if not properly managed or if the patient is not well-controlled.

Question 266: A 45-year-old man with chronic obstructive pulmonary disease (COPD) is experiencing worsening symptoms despite using short-acting bronchodilators. Which long-acting beta-agonist could be recommended for maintenance therapy?

A. Albuterol
B. Salmeterol (Correct Answer)
C. Pirbuterol
D. Orciprenaline

Explanation: ***Salmeterol*** - Salmeterol is a **long-acting beta-agonist (LABA)**, indicated for maintenance therapy in COPD due to its prolonged bronchodilatory effect. - LABAs like salmeterol are crucial for **symptom control and reducing exacerbations** in patients with persistent COPD symptoms. *Albuterol* - Albuterol is a **short-acting beta-agonist (SABA)**, primarily used for **rescue relief** of acute bronchospasm, not for maintenance therapy. - Its effects last for only 4-6 hours, making it unsuitable for sustained symptom control in COPD. *Pirbuterol* - Pirbuterol is also a **short-acting beta-agonist (SABA)**, similar to albuterol, providing quick but temporary relief. - It is not recommended for daily, long-term maintenance treatment of COPD. *Orciprenaline* - Orciprenaline is an older, **short-acting beta-agonist** no longer commonly used due to a less favorable side effect profile and shorter duration of action. - It is not considered a modern first-line treatment for either acute relief or maintenance in COPD.

Question 267: In which condition is the use of PGF2α analogues contraindicated?

A. Glaucoma
B. Bronchial asthma (Correct Answer)
C. Priapism
D. Post partum hemorrhage

Explanation: ***Bronchial asthma*** - PGF2α analogues, particularly **carboprost**, are **uterotonics** that can cause **bronchoconstriction** and are thus contraindicated in patients with **bronchial asthma**. - This effect is due to the activation of prostanoid receptors in the airways, leading to the constriction of bronchial smooth muscle. *Postpartum hemorrhage* - **PGF2α analogues** like **carboprost** are frequently used to treat **postpartum hemorrhage** due to their potent uterotonic effects, which help to contract the uterus and stop bleeding. - This condition is an **indication**, not a contraindication, for PGF2α analogue use. *Glaucoma* - **Prostaglandin analogues** (e.g., latanoprost, travoprost), which are often PGF2α derivatives, are a **first-line treatment for glaucoma** as they effectively lower **intraocular pressure**. - Therefore, glaucoma is an **indication** for some PGF2α analogues, not a contraindication. *Priapism* - **PGF2α analogues** are generally **not directly implicated in the treatment or contraindication of priapism**, which is often managed with alpha-agonists, aspiration, or surgical shunts. - While prostaglandins (like PGE1) can induce erections, PGF2α analogues are not typically used in this context and do not pose a direct contraindication for priapism.

Question 268: Advantage of formoterol over salmeterol is?

A. It has got a faster onset of action (Correct Answer)
B. Both can be used for prophylaxis in asthmatics
C. It is a long-acting beta 2 agonist
D. It has minimal beta 1 agonistic action

Explanation: ***It has got a faster onset of action*** - **Formoterol** has a **faster onset of action** (within 1-3 minutes) compared to salmeterol, making it suitable for both maintenance and quick relief of bronchoconstriction. - This rapid onset allows it to act similarly to short-acting beta-agonists (SABAs) for symptom control, while also providing long-acting benefits. *Both can be used for prophylaxis in asthmatics* - While both **formoterol** and **salmeterol** are **long-acting beta-2 agonists (LABAs)** [1] and are used for prophylaxis (maintenance therapy) in asthma, this statement does not highlight an advantage of formoterol over salmeterol. - Their primary role is in preventing symptoms, not necessarily in acute relief due to this shared characteristic. *It is a long-acting beta 2 agonist* - Both **formoterol** and **salmeterol** are **long-acting beta-2 agonists** [1]. - This is a shared characteristic and not a unique advantage of formoterol over salmeterol. *It has minimal beta 1 agonistic action* - Both **formoterol** and **salmeterol** are *highly selective* for **beta-2 receptors** [1], meaning they both have minimal beta-1 agonistic action. - Therefore, this is not a distinguishing advantage of formoterol over salmeterol.

Question 269: Which of the following is NOT an inhalational steroid?

A. Beclomethasone
B. Budesonide
C. Fluticasone acetonide
D. Betamethasone (Correct Answer)

Explanation: ***Betamethasone*** - **Betamethasone** is a potent **systemic corticosteroid** commonly used orally, parenterally, or topically for various inflammatory conditions. - It is **not formulated for inhalation** due to its systemic activity which would lead to significant side effects if administered via the respiratory tract. *Beclomethasone* - **Beclomethasone** is a well-known **inhaled corticosteroid (ICS)** used for maintenance therapy in asthma and COPD. - It works by reducing airway inflammation locally with minimal systemic absorption. *Budesonide* - **Budesonide** is another widely used **inhaled corticosteroid (ICS)**, effective in managing asthma and COPD. - It is also available in nebulized formulations for children and individuals unable to use metered-dose inhalers. *Fluticasone acetonide* - **Fluticasone acetonide** is a potent **inhaled corticosteroid (ICS)** frequently prescribed for long-term control of asthma and allergic rhinitis. - It has high topical anti-inflammatory activity and low systemic bioavailability, making it suitable for inhalation.

Question 270: Which of the following is not an anti histaminic drug of the ethanolamine group?

A. Chlorpheniramine (Correct Answer)
B. Diphenhydramine
C. Clemastine
D. Dimenhydrinate

Explanation: ***Chlorpheniramine*** - belongs to the **propylamine chemical class** of antihistamines. - It is a first-generation antihistamine known for its modest **sedative effects** and significant **anticholinergic activity**. *Clemastine* - is a first-generation antihistamine of the **ethanolamine class**. - It is known for its relatively **long duration of action** and pronounced **sedative** and **anticholinergic effects**. *Diphenhydramine* - is a classic first-generation antihistamine belonging to the **ethanolamine class**. - It is commonly used for **allergies**, **insomnia**, and **motion sickness** due to its strong **sedative** and **anticholinergic properties**. *Dimenhydrinate* - is a salt of **diphenhydramine** and 8-chlorotheophylline, and thus falls under the **ethanolamine class** as its primary active component. - It is primarily used to prevent and treat **nausea**, **vomiting**, and **dizziness associated with motion sickness**.

Practice by Chapter

Bronchodilators

Practice Questions

Corticosteroids in Respiratory Disorders

Practice Questions

Anti-inflammatory Respiratory Agents

Practice Questions

Mast Cell Stabilizers

Practice Questions

Leukotriene Modifiers

Practice Questions

Antitussives and Expectorants

Practice Questions

Nasal Decongestants

Practice Questions

Pulmonary Surfactants

Practice Questions

Drugs for Pulmonary Hypertension

Practice Questions

Oxygen Therapy

Practice Questions

Want unlimited practice?

Get full access to all questions, explanations, and performance tracking.

Start For Free