Respiratory Drug : INI-CET Quick Revision Guide

Drugs for Pulmonary Arterial Hypertension (PAH)

Mnemonic- PEPSI Coca Cola

PG-1 analogs

• T – Treprostinil
• I – Iloprost
• E – Epoprostenol
• Route: IV or inhalation (Not oral)

Endothelin receptor antagonists (drugs end with “Entan”)

• Bosentan, Sitaxsentan: Blocks both ETA/ETB receptors
• Ambrisentan: Blocks ETA receptors
• Route: Given orally
• Contraindicated in pregnancy due to high teratogenicity

PDE 5 inhibitors

• Increased cGMP levels
• Drugs
  • Sildenafil (Viagra): Also used for erectile dysfunction
  • Tadalafil
• Route: Oral

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Soluble guanylyl cyclase activators

• Increases cGMP levels
• Drugs
  • Riociguat
  • New drugs – Vericiguat for congestive heart failure

I - Prostaglandin agonist

Selexipag (Oral drug)

Continuous NO inhalation

Treatment of Pulmonary artery hypertension (PAH)

Calcium channel blockers

Amlodipine, nifedipine: Pulmonary artery hypertension (PAH)

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Drugs for Cough

Cough- Protective reflex

Has three types of drugs

Demulcents

• Inhibit the afferent or irritant impulse to the bronchus
• Soothens the airway
• These are lozenges, linctuses, glycerine

Expectorants

• Reduce mucus viscosity
  • Liquify the mucus
  • Expel the mucus as sputum
• Recommended in productive or infective cough
• Divided into two types of drugs
  • Mucokinetic- Increase the ciliary movements
    • Drug- Guaifenesin
  • Mucolytic- Liquify the mucus
    • MOA- Break the disulfide bond
    • Drugs include
      • Bromhexine (Pro drug)
      •  Ambroxol (Active form)
      • N acetyl cysteine
      • Carbocisteine
      • Erdosteine

Anti-tussives

• Directly suppress the cough
• Recommended in dry or allergic cough
• Contraindication Infective cough

Drugs for Cystic Fibrosis

• Disease modifying therapy—Correct CFTR channels
• It prolongs the life expectancy of the patient
• Drugs
  • Lumacaftor or tezacaftor
  • Ivacaftor
  • Elexacaftor
• Combination of three drugs is recommended: Trikafta

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Symptomatic Treatment

• Blockage of gland ducts - Dry eyes, mouth (Xerophthalmia, xerostomia)
  • Drugs - Pilocarpine, cevimeline
• Hard mucus
  • Drugs - Mucolytics
    • N acetyl cysteine
    • Erdosteine
    • Carbocysteine
    • Dornase alpha (Degrades DNA)
    • Hypertonic saline
• Recurrent pneumonia- Pseudomonas pneumonia
  • Drugs - Inhalational antibiotics
    • Tobramycin- Aminoglycoside
    • Amikacin
    • Colistin
    • Aztreonam
• Chronic pancreatitis—Malabsorption can lead to chronic diarrhea
  • Drugs - Pancreatic enzyme replacement (Pancrezyme)

Asthma

Anti-inflammatory drugs (Maintenance therapy)

· Used in prevention for chronic or persistent asthma

• Prevent the recurrent attack of asthma (Secondary attack)
• Drugs
  • Mnemonic—M Lo L C M
    • Mast cell stabilizers
    • LOX inhibitor
    • Leukotriene receptor antagonist
    • Corticosteroids
    • Monoclonal antibodies-(MAB)

Bronchodilators (Reliever therapy)

• Used during the acute attack of asthma
• Drugs include
  • Mnemonic- BAT Man
    • Beta 2 agonists
    • Anticholinergic
    • Theophylline
    • Magnesium sulfate

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Inflammation in Type 1 hypersensitivity

Antigen binds to the IgE antibody

↓

Mast cells release the various inflammatory mediators (Degranulation)

↓

LTC and LTD Acts on bronchus 4 4

↓

Acts on the receptor called CYS LT receptor 1

↓

Bronchoconstriction/Asthma

↓

LTB , IL-5, IL-4 recruit white blood cells (eosinophils). 4

↓

Inflammation

Inflammatory mediators

• Mast cell stabilizers: Inhibit the release of inflammatory mediators (-CROM-)
• LOX inhibitor: Drug- Zileuton
• Leukotriene receptor antagonist (LRA) : · Blocks CYS LT1 receptor of leukotriene, Drugs- (-Lukast-)
• Corticosteroids: Broad spectrum anti inflammatory drugs
• Monoclonal antibodies:
  • Blocks IgE antibody- Omalizumab
  • Blocks IL-5- Mepolizumab, Reslizumab
  • Blocks IL-5 receptor- Benralizumab
  • Blocks IL-4- Dupilumab

Chronic or Persistent Asthma

Beta-2 Agonist

Mechanism of Action of Beta 2 Agonists

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Adverse Effects of β₂ Agonists

• Mnemonic 3H and 2T
  • Hypoxia—Due to ventilation-perfusion mismatch
  • Hyperglycemia– Breakdown of glycogen
  • Hypokalemia
  • Tachycardia—manifests as palpitations
  • Tremors—Most common

Mechanism of Action of Anticholinergic Drugs 

Bronchus has an M receptor (Acetylcholine) 3

↓

Stimulation of the receptor

↓

Bronchoconstriction

↓

Blockage of the receptor

↓

Bronchodilation

Drugs include

• Ipratropium
• Tiotropium
• Oxitropium
• Umeclidinium
• Aclidinium

Side Effects

• Dry eyes/mouth
• Dry mucus
• Constipation
• Urinary retention

Theophylline 

• It is a naturally occurring molecule, Non specific PDE inhibitor
• It is a Natural- Methylxanthines
• Methylxanthines contains three molecules
  • Theophylline- Maximum present in Caffeine
    • Has peripheral action
    • Shows more action on bronchus

Mechanism of Action of Theophylline

Mnemonic- PANCHI

• P- Phosphodiesterase 4 inhibitor
  • Increase in the levels of cAMP- Bronchodilation
• A- Blocks Adenosine (A ) receptor leads to bronchodilation 1
• N- Inhibit NF kappa B
• C- Calcium channel blocked
• H- Causes Histone acetylation
  • Decrease the inflammation of IL-5, IL-4
• I- Reduces the inflammation

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Anti Inflammatory Drugs

Mast cell stabilizers

Drugs include

• Nedocromyl
• Chromoglycate
  • Other Name: Cromolyn

Aspirin Induced Asthma

Corticosteroids 

• Broad spectrum anti-inflammatory drugs
• Disadvantage- Not a bronchodilator

Asthma Phenotypes

Monoclonal antibodies in Asthma

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