Inhaled Corticosteroids

• Introduction 

• Illustrated mechanism of action 

• Examples of Medication Brand Names (with Images)

• Indication

• Side Effects 

• Precautions & Contraindications 

• Monographs

• Reference 

Inhaled Corticosteroids (ICS) :are the most effective long-term treatment for managing persistent asthma and preventing exacerbations.

They reduce inflammation and swelling in the airways, helping to control symptoms like wheezing and shortness of breath.

Regular use of ICS improves lung function, decreases airway sensitivity, and significantly lowers the risk of asthma attacks.Because of their effectiveness, ICS are considered the foundation of asthma treatment in both adults and children.

1956:

The pressurized metered-dose inhaler (pMDI) was introduced, allowing effective delivery of asthma medications directly to the lungs. It was initially used to deliver non-selective beta-agonists like adrenaline and isoprenaline, which only provided short-term symptom relief.

1960s:

A rise in asthma-related deaths raised safety concerns about these medications. This led to the development of selective short-acting beta-agonists such as salbutamol, which were safer and more effective.

Early 1970s:

The first inhaled corticosteroid (ICS), beclomethasone dipropionate (BDP), was introduced.

This was a major breakthrough, as ICS targeted airway inflammation, the root cause of asthma—not just the symptoms.

After the 1970s:

ICS became the standard long-term treatment for asthma. Treatment regimens improved from multiple daily doses to twice-daily use, which increased patient adherence and maintained effectiveness.

Today:

ICS are considered the cornerstone of asthma management, offering better control, fewer exacerbations, and a safer alternative to systemic steroids.

1. Cellular Entry and Activation:

ICS cross cell membranes and bind to cytoplasmic glucocorticoid receptors (GRs).

The activated GR complex translocates into the nucleus.

2. Genomic Effects:

Inside the nucleus, the GR complex binds to glucocorticoid response elements (GREs) on DNA.

This leads to:

Induction of anti-inflammatory genes.

Repression of pro-inflammatory genes, including those for cytokines, chemokines, adhesion molecules, and inflammatory enzymes.

3. Suppression of Inflammation:

ICS inhibit key proinflammatory transcription factors such as NF-κB and AP-1.

This reduces recruitment and survival of inflammatory cells in the airways.

4. Nongenomic (Rapid) Effects:

ICS also cause rapid effects such as transient vasoconstriction in airway vessels.

This decreases airway blood flow and reduces edema quickly.

Overall Outcome:

Reduced airway inflammation, edema, and hyperresponsiveness.

Improvement in asthma symptoms and lung function.

1. Bronchial Asthma

First-line maintenance therapy for persistent asthma (mild, moderate, or severe).

Used regularly to control airway inflammation, reduce symptoms, and prevent exacerbations.

Not used for acute attacks.

2. Chronic Obstructive Pulmonary Disease (COPD)

Indicated in moderate to severe COPD with:

Frequent exacerbations (≥2/year or ≥1 requiring hospitalization).

Eosinophilic phenotype (blood eosinophils ≥300 cells/µL, or ≥100 with frequent exacerbations).

Always used in combination with long-acting bronchodilators (LABA ± LAMA).

3. Other Less Common Indications:

Allergic Bronchopulmonary Aspergillosis (ABPA)

Eosinophilic Bronchitis

Cough Variant Asthma

Exercise-induced bronchospasm (when other treatments are ineffective)

Post-infectious cough (in selected cases

Local Side Effects of Inhaled Corticosteroids (ICS):

-Hoarseness

-Sore throat

-Cough

-Oral thrush (fungal infection in the mouth)

Contraindications
1. Active or Latent Tuberculosis: ICS may worsen TB infections.

2. Hypersensitivity Reactions: Discontinue immediately if signs of allergy appear (e.g., rash, anaphylaxis).

3. Immunosuppression: Use cautiously in patients with existing infections due to the risk of exacerbation.

4. Switching from Systemic Corticosteroids: Requires gradual tapering and close monitoring to avoid adrenal insufficiency.

5. History of Recurrent Pneumonia: ICS may not be suitable for patients with repeated pneumonia episodes.

6. Use with CYP3A4 Inhibitors: Co-administration with strong CYP3A4 inhibitors (e.g., ketoconazole) may increase systemic steroid exposure—use caution.

precautions
1. Monitor for Side Effects: Regularly check for potential adverse effects during treatment.

2. Use the Lowest Effective Dose: Minimizes the risk of side effects while maintaining symptom control.

3. Ensure Proper Inhaler Technique: Essential for effective symptom control and to avoid complications.

4. Monitor Growth in Children: Long-term use may affect growth, so regular height checks are recommended.

5. Consider Bone Health: ICS can decrease bone mineral density, especially with long-term use.

6. Watch for Drug Interactions: Caution with medications like diuretics or diabetes drugs that may interact with ICS.

7. Extra Care in Elderly Patients: Older adults may be more sensitive to side effects and require closer monitoring.

8. Monitor for Oral Thrush: ICS can increase the risk of oral candidiasis (thrush). Patients should rinse their mouth after use.

9. Caution in Pregnant and Lactating Women: Use cautiously in pregnant or breastfeeding women, as the risks and benefits must be carefully weighed.

https://youtu.be/L6MtAAS1Fuo?si=q-fk4Wv661EzjXqD

https://youtu.be/BT516MnZJ7s?si=43Rn_2RC39oW_KVu

https://www.ncbi.nlm.nih.gov/books/NBK470556/

https://www.healthline.com/health/inhaled-steroids
https://youtu.be/4ZZAnPLwPgQ?si=XzCRvEzZImlbCjZO

https://youtu.be/QhmC_Kp6mko?si=S-sc0IZCfkBSIXk1