Understanding Drugs and Asthma

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Questions and Answers

What is the primary mechanism of action of short-acting β2-adrenoceptor agonists (SABA) like Salbutamol?

Inhibit TNF-α release from monocytes

Act as anti-inflammatory agents

Stimulate α-adrenoceptors

Dilate bronchioles (correct)

Which of the following treatments is classified as Regular Preventer Therapy for asthma?

Salbutamol

Long-acting muscarinic antagonist (LAMA)

Leukotriene Receptor Antagonist (oral)

Low dose corticosteroid (inhaled) (correct)

What is the duration of action for short-acting β2-adrenoceptor agonists (SABA) like Terbutaline?

12 hours

3-5 hours (correct)

6-8 hours

1-2 hours

Which of these actions is NOT associated with SABA usage?

Long-term reduction of airway inflammation Signup and view all the answers

What type of inhaler propellant is used in SABA metered dose aerosols?

Hydrofluoroalkanes (HFA) Signup and view all the answers

What is the primary mechanism of action of montelukast?

Inhibits leukotriene receptors, especially CysLT-1 Signup and view all the answers

Which of the following adverse effects is commonly associated with montelukast?

Diarrhea and gastrointestinal discomfort Signup and view all the answers

Under what conditions is the use of long-acting β2-adrenoceptor agonists (LABAs) recommended?

In combination with inhaled corticosteroids for maintenance therapy Signup and view all the answers

What is a possible neuropsychiatric adverse effect of montelukast?

Speech impairment and obsessive-compulsive symptoms Signup and view all the answers

Which medication is NOT typically used in combination with inhaled corticosteroids?

Long-acting muscarinic cholinoceptor antagonists Signup and view all the answers

What is the role of Interleukin 5 (IL-5) in asthma?

It attracts eosinophils to the airways. Signup and view all the answers

How are monoclonal antibodies against Interleukin 5 administered?

By subcutaneous injection or IV infusion. Signup and view all the answers

Which of the following drugs is classified as a short-acting β2-adrenoceptor agonist (SABA)?

Salbutamol Signup and view all the answers

Which treatment strategy involves the use of a leukotriene receptor antagonist?

Initial add-in therapy Signup and view all the answers

What potential complications can arise from prolonged use of oral corticosteroids in adults with severe asthma?

Increased risk of diabetes and high blood pressure. Signup and view all the answers

What is the primary action of long-acting muscarinic receptor antagonists (LAMA) like Tiotropium?

Block muscarinic receptors Signup and view all the answers

Which of the following adverse effects is associated with glucocorticoids like prednisolone?

Adrenal suppression Signup and view all the answers

Which mechanism is responsible for the anti-inflammatory effects of prednisolone?

Inhibition of IL-2 transcription Signup and view all the answers

What is a potential consequence of saturating liver metabolism when taking medications such as aminophylline?

Increased risk of drug interactions Signup and view all the answers

Which of the following is NOT an effect attributed to using corticosteroids like prednisolone?

Increased inflammation Signup and view all the answers

What is highlighted as an essential therapeutic window for drugs like aminophylline?

10-20 mg/L Signup and view all the answers

Severe asthma can lead to which of the following issues?

Constant breathlessness Signup and view all the answers

What is the role of adenosine receptor antagonism in bronchodilators?

Promote cAMP increase Signup and view all the answers

What is a key adverse effect associated with the use of SABA?

Hypokalemia Signup and view all the answers

Which inhaler type is designed to be more user-friendly by being breath-activated?

Spacer Signup and view all the answers

What is a potential consequence of long-term use of β2-agonists?

Tolerance to salbutamol Signup and view all the answers

Which of the following inhaled corticosteroids may cause oral candidiasis?

Beclometasone Signup and view all the answers

Which is an initial step in the regular preventer therapy for asthma?

Short acting β2-adrenoceptor agonist as required Signup and view all the answers

What is one significant problem with using inhaled corticosteroids?

May cause adrenal suppression Signup and view all the answers

How long does it typically take for inhaled corticosteroids to display their full effect?

3-7 days Signup and view all the answers

What is an adverse effect raised by the use of long acting β2-adrenoceptor agonists?

Increased risk of pneumonia Signup and view all the answers

Study Notes

Drugs and Asthma

Asthma involves the narrowing and inflammation of airways, leading to breathing difficulties.
Different drugs target different aspects of asthma, including inflammation, bronchoconstriction, and mediator release.

Asthma

Asthma involves airways that become narrowed and inflamed.
The diagram shows normal airways, asthmatic airways during attack, and relaxed smooth muscles in a healthy state.
Air becomes trapped in the alveoli and smooth muscles tighten during an attack.

Drug Treatment of Asthma

Intermittent Reliever Therapy: Short-acting β2-adrenoceptor agonists (SABA) are used for rapid relief.
Regular Preventer (Maintenance) Therapy: Low-dose inhaled corticosteroids are used regularly for long-term control, alongside other options.
Initial Add-In Therapy: Leukotriene Receptor Antagonists (oral) and long-acting β2-adrenoceptor agonists (LABA) can be added to the above for particular cases.
Additional Controller Therapy: Long-acting muscarinic antagonists (LAMA) and theophylline can be used in some scenarios.
Continuous corticosteroid therapy: Prednisolone is an example of an oral continuous corticosteroid.

Inhalers, Spacers and Nebulisers

MDI spacers help improve delivery of medication.
Spacers reduce the amount of medication that's deposited in the mouth and throat.
Spacers help improve medication delivery to the lungs.

Short-acting β2-adrenoceptor agonists (SABA)

Examples include salbutamol and terbutaline.
These drugs act on β2 receptors in the lungs.
They cause smooth muscle relaxation, widening airways .

SABA – Mechanism of Action

Salbutamol and Terbutaline bind to β2-adrenoceptors on airway smooth muscle cells.
This triggers a cascade of intracellular events that lead to smooth muscle relaxation.
Resulting in bronchodilation.

SABA - Metered Dose Aerosol

The medication is delivered via inhaler, as a pressurized suspension, with propellant.
Propellants are hydrofluoroalkanes, not CFCs.
Mechanisms: The drug dilates bronchioles, promotes immediate relief, has a duration of 3-5 hours, and reduces mediator release from mast cells.
In addition, these may inhibit TNF-alpha and increase mucus clearance.

Inhaler vs Spacer

Using a spacer with an inhaler improves deposition in the lungs and reduces oropharyngeal deposition.
The correct technique for using a metered-dose inhaler with a spacer is demonstrated.

Breath-activated Inhalers

Different types of breath-activated inhalers are discussed, including Autohalers, Accuhalers, Turbohalers, and Diskhalers.
These inhalers deliver medication as dry powder.

SABA - Adverse Effects

Side effects include tachycardia, hypokalaemia, tremor, and tolerance.
Genetic polymorphisms can influence the response to the treatment.

Regular Preventer (Maintenance) Therapy

Treatment involves a short-acting β2 agonist as needed, and a low-dose inhaled corticosteroid as a component of the preventative therapy.
Treatment is scaled accordingly if symptoms are more frequent.

Inhaled Corticosteroids

Types include beclometasone dipropionate, fluticasone, and budesonide.
These reduce inflammation in the airways.

Inhaled steroids

Inhaled steroids have a slow onset of action (3-7 days).
They are not bronchodilators, offering no immediate relief.
Oral candidiasis is a potential side effect.
The amount absorbed systemically can be reduced by using a spacer.

Step 3 Initial Add-In Therapy

This involves adding a leukotriene receptor antagonist (oral) and a long-acting β2-adrenoceptor agonist (inhaled LABA) to the existing preventative treatment.

A. An ORAL asthma agent - montelukast

Montelukast is an oral leukotriene receptor antagonist.
Reduces inflammation and bronchoconstriction.

Leukotrienes

Leukotrienes are inflammatory mediators.
Blockade/inhibition of leukotrienes provides relief.

Montelukast – A Leukotriene Receptor Antagonist

Montelukast is a cysLT1 receptor antagonist.
This drug reduces inflammation, including reduced airflow obstruction, bronchoconstriction, and inflammatory cell infiltration, in the airways.
Common side effects include gastrointestinal issues, skin reactions, and upper respiratory tract infection.
Potential for neuropsychiatric risk should be considered

B. Long acting β2-adrenoceptor agonists (LABA)

Include formoterol and salmeterol.
Long-term control of asthma symptoms.

Maintenance and Reliever Therapy (MART)

Combines inhaled corticosteroids with LABAs for combination therapy.

4. Additional Controller Therapies

Additional controllers may include long-acting muscarinic antagonists (LAMAs) and theophylline.
Theophylline is taken orally.

B. Long-acting muscarinic receptor antagonist (LAMA)

This drug (Tiotropium) is a long-acting muscarinic receptor antagonist delivered via inhaler to reduce bronchoconstriction.
Reduces inflammation and bronchoconstriction.

Theophylline

It is a bronchodilator that relaxes airway smooth muscle and has other beneficial effects, given orally.
It is administered twice daily.

Step 5: Continuous corticosteroid (oral)

Specialist therapy involves oral prednisolone.
Prednisolone is an anti-inflammatory and immunosuppressant.

Prednisolone

Prednisolone is an oral corticosteroid that blocks the synthesis of inflammatory substances, like prostaglandins and leukotrienes in the airways (with resulting anti-inflammatory and immunosuppressant effects).
It reduces inflammation and the immune response.
Potential side effects include adrenal suppression, requiring careful monitoring and gradual tapering of the dose.

Adverse Effects : Glucocorticoids

Possible side effects of glucocorticoids include euphoria in some, thin arms, legs and muscle wasting, buffalo hump, increased abdominal fat, cataracts, skin thinning and easy bruising, and more.
Possible side effects include osteoporosis, hyperglycaemia, negative nitrogen balance, increased appetite, increased susceptibility to infection and obesity.

Adrenal Suppression

Sudden withdrawal of prednisolone can cause adrenal suppression.
Patients should be monitored and slowly taper off the drug.

Severe Asthma and The Eosinophil

Severe asthma is characterized by frequent attacks and/or a need for oral steroids.
Eosinophils are immune cells that play a role in asthma inflammation.

Interleukin IL-5 Inhibitors

These drugs block the action of Interleukin-5 (IL-5), which is important for eosinophil activation/recruitment.
Includes monoclonal antibodies like Nucala (mepolizumab) which is used for subcutaneous injection every 4 weeks.

Major drugs to remember for the treatment of Asthma

Salbutamol, Beclometasone, Montelukast, Salmeterol, Tiotropium, Theophylline, Prednisolone, and Mepolizumab are major drugs to treat asthma.

Summary: Drug Treatment of Asthma

Short-acting β2-agonists (SABA) for rapid relief.
Regular preventers (maintenance) with inhaled corticosteroids for long-term control.
Initial add-ins such as Leukotriene receptor antagonists or long-acting β2-agonists (LABAs) are added according to specific cases.
Additional controller therapies such as long-acting muscarinic antagonists(LAMAs) and theophylline may be used in specific cases.
Continuous corticosteroid therapy with Prednisolone may be considered under specialist care.

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Description

This quiz explores the role of various drugs in managing asthma. It covers the pathophysiology of asthma, including airway inflammation and the types of medications used for both immediate relief and long-term control. Test your knowledge on asthma treatments and their mechanisms.