Drugs for Bronchial Asthma (Part 02) Flashcards
Two Classifications of Drugs for Asthma
- Reliever
• It increase Airway Caliber - Controller
• Anti-Inflammatory Agents
Drug/s for Asthma under Reliever
- Beta 2 Agonists
- Methylxanthines
- Anticholinergics
Drugs for Asthma under Controller
- Inhaled Corticosteroids
- Leukotriene Antagonists
- Mast Cell Stabilizers
Mechanism of Action of Beta 2 Agonists
– Stimulating Beta 2 Receptors
– Activating Adenyl Cyclase
– ↑ Intracellular Production of cAMP
Two Types of Beta 2 Agonists
- Short-Acting Beta 2 Agonists
• Reliever – (Manage) - Long-Acting Beta 2 Agonists
• Controller - (Prevent)
It has short duration but with rapid onset of action. It is considered as the primary reliever medication. The first line in the treatment of acute exacerbation of bronchial asthma.
Short-Acting Beta 2 Agonists
Example of Drug/s under Short-Acting Beta 2 Agonists that are Available as Inhalers, and given as Oral Tablet.
• Salbutamol (Ventolin)
• Terbutaline (Bricanyl)
Two Classifications of Long-Acting Beta 2 Agonists
- Long Acting with Slow Onset
- Long Acting with Rapid Onset
Example of Drug/s under Long Acting with Slow Onset, and the only Beta 2 Agonist administered Orally without Inhalation Route.
Bambuterol (Bambec)
Example of Drug/s under Long Acting with Rapid Onset.
• Formoterol
• Salmeterol (Serevent)
It has the generic name of Seretide.
Salmeterol + Fluticasone
It has the generic name of Symbicort.
Formoterol + Budesonide
A/E of Beta 2 Agonists
- Skeletal Muscle Tremor
- Nervousness
- Occasional Weakness
Toxicities of Beta 2 Agonists
- Tachyphylaxis
- Cardiac Arrhythmias
- Hypoxemia
These are bronchodilators that are reserved for special situations, and are non-selective agonists of adrenergic receptors.
Sympathomimetic Agents
Examples of Sympathomimetic Agents
- Epinephrine
- Isoproterenol (Isoprenaline)
- Ephedrine
Its MOA is to stimulate catecholamine receptor. It is an effective, rapidly acting bronchodilator.
Epinephrine
Use of Epinephrine
Anaphylactic Shock
A potent bronchodilator, and has duration of action from 60 to 90 minutes.
Isoproterenol (Isoprenaline)
Mechanism of Action of Ephedrine
– Increase Catecholamine Release
– Inhibition of Reuptake
Alternative controller medication because it possesses narrow therapeutic index. Drug/s for the treatment of COPD (usually given at bedtime).
Methylxanthines
At high concentrations, they inhibit several members of the PDE enzyme family. At low doses, they inhibit the late phase of allergic reaction and they may actually have anti-inflammatory activity.
Methylxanthines
A synthetic analog of Theophylline.
Dyphylline
It is not for asthma but for intermittent claudication.
Phentoxyfylline
It competitively inhibit the effect of acetylcholine at muscarinic receptors thus blocking the contraction of the airway smooth muscle, and the first line reliever in COPD.
Anticholinergics
Example of Drug/s associated with Anticholinergics.
- Ipratropium (Atrovent)
- Tiotropium
- Oxytropium
An Anticholinergic Drug with 24-hour Duration of Action (Long Acting)
Tiotropium
It has the generic name of Berodual.
Ipratropium + Fenoterol
It has the generic name of Combivent.
Ipratropium + Salbutamol
Prophylactic Agents for Asthma, and used as Prophylaxis of EIB.
Mast Cell Stabilizers
Example of Drug/s associated with Mast Cell Stabilizers.
• Cromolyn (Intal)
• Nedocromil (Tilade)
It poorly absorbed from GIT and must be inhaled as microfine powder or aerosolized solution.
Cromolyn (Intal)
It has very low bioavailability and is available only in metered-dose aerosol form.
Nedocromil (Tilade)
One of the A/E of Mast Cell Stabilizers
Bronchospasm
It inhibits 5-lipoxygenase thereby preventing leukotriene synthesis.
5-LOX Inhibitor
A drug that is under 5-LOX Inhibitor—is the least prescribed because of the requirement of four (4) times daily dosing and because of occasional liver toxicity.
Zileuton (Zyflo)
Prevents the binding of LTD4 to its specific receptor thus inhibiting its effects on airways.
Leukotriene Antagonists
A selective Cysteinyl Leukotriene 1 (CysLT1) receptor antagonists.
Leukotriene Antagonists
Example of Drug/s associated with Leukotriene Antagonists.
• Montelukast (Singulair)
• Zafirlukast (Accolate)
It has the generic name of Co-Altria.
Montelukast + Levocetirizine
Precaution: The chewable forms of this drug (4 to 5 mg tablets) contain Aspartame and should be avoided in patients with Phenylketonuria.
Montelukast (Singulair)
A/E of Leukotriene Antagonists
- Mask the Symptom of Churg-Strauss Syndrome
- Phenylketonuria
A systemic vasculitis characterized by worsening asthma, pulmonary infiltrates, and eosinophilia.
Churg-Strauss Syndrome
Inhibits Phospholipase A2
Corticosteroids
Steroids Used in Bronchial Asthma
• Long Acting (Inhaled)
• Systemic Oral Medications
• Systemic Parenteral
Example of Drug/s under Long Acting (Inhaled).
• Budesonide
• Beclomethasone
• Fluticasone
• Flunisolide
Example of Drug/s under Systemic Oral Medications.
Prednisone / Prednisolone
Example of Drug/s under Systemic Parenteral.
• Hydrocortisone
• Methylprednisone
Steroids that are First Line Controller Medications.
Long Acting (Inhaled)
Steroids that are Short Acting Agents.
Systemic Oral Medications
Steroids that are Preferred Agents for Status Asthmaticus.
Systemic Parenteral
A life-threatening condition that occurs when severe asthma exacerbation fails to respond to usual treatment.
Status Asthmaticus
Disorder that occurs when the body makes to much of the hormone cortisol over long period of time.
Cushing-Like Syndrome
A drug under Anti-IgE Monoclonal Antibodies. Inhibits the binding of IgE to mast cells.
Omalizumab
Example of Drug/s under Metered Dose Inhalers (MDIs).
• Triamcinolone (Azmacort)
• Salbutamol (Ventolin)
Additions of spacer in patient with poor MDI technique improves pulmonary delivery of the agent.
Spacers and Holding Chambers
A flat, round device that is used to deliver asthma medicines in powder form.
Diskus Inhaler
They are used to avoid the use of Freon propellants. They are also being used more frequently because many patients find them easier to use than an MDI.
Dry-Powder Inhalers
A breath-activated device.
Turbuhaler
An example of drug for turbuhaler.
Formoterol + Budesonide = Symbicort
It requires less patient coordination during administration of multiple inhalations.
Nebulizers
Although the Fraction of Inspire Oxygen (FIO2) administered is based on the patient’s arterial blood gas status, 1-3 L / min is generally given via facemask or nasal cannula.
Humidified Oxygen
A mixture of helium and oxygen that has lower density than air.
Heliox
It may be required if the patient is volume depleted.
Intravenous Fluids and Electrolytes
Some measures include use of allergen-resistant mattress and pillow encasements, use of high-filtration vacuum cleaners, removal of carpets and draperies, and avoidance of furry pets.
Environmental Control
