Drugs For Asthma_martinez

DRUGS FOR ASTHMA STUDENT DOC MARTINEZ – AT STILL UNIVERSITY, SCHOOL OF OSTEOPATHIC MEDICINE

A N T I I M M F L A M A T O R I E S

GLUCOCORTICOIDS – For acute and for maintenance management TYPE

MOA

Beclomethas one Methylpredni sone

Suppress Inflammation by Reversing mucosal edema, ↓capillary permeability, Inhibit release of leukotrienes and cytokines  ↓ Bronchial Hyper responsiveness

& Prednisone

ADEM

Inhalation (less systemic) Oral & parenteral

SYTEMIC ADVERSE

ADVERSE EFFECTS

USE

Suppression of hypothalamicpituitary-adrenal

Glucocorticoids have effects on virtually every

Chronic Asthma… Not acute

organ in the body

Acute exacerbations and Tx of chronic severe asthma

Growth Suppression

Systemic administration can cause numerous, at

Osteoporosis

times serious, side effects (reserve use for severe allergic reactions)

↑intraocular pressure

Most effective anti-asthmatic drugs

Oral Canidasis

Observe usual precautions for steroid use, i.e., avoid rapid withdrawal; use every-other-day therapy when symptoms are controlled

Horaseness

Altered bone metabolism. MODULATORS OF HISTAMINE RELEASE TYPE

Cromylin

MOA

Blocks release of inflammatory mediators from mast cells and basophils.

Use prophylactically not effective for 2-6 weeks. Omalizum ab

Recombinant humanized (chimeric) monoclonal IgG antibody directed against circulating IgE

ADVERSE EFFECTS

USE

Powder & solution for inhalation; NOT effective orally

Alternative Tx for mild persistent asthma.

Minimal adverse reactions bronchoconstriction, cough, wheezing

Preventive tx prior to exercise or unavoidable exposure to known allergens

Intravenous or subcutaneous administration every 2–4 weeks

Recognizes specific Fc portion of IgE that binds to the high-affinity IgE receptors (Fc-epsilon RI) blocking binding of IgE to mast cells and basophils

Can cause headache and injection site reactions

Decreases circulating free IgE

L E U K O T R I E N E

COMPETITIVE LEUKOTRIENE RECEPTOR ANTAGONISTS Montelukl Competitive antagonist at the cysLT1 GI upset

M O D I F I E R S

INHIBITORS OF 5–LIPOXYGENASE Zileuton Blocks 5-lipoxygenase  ↓ leukotriene synthesis

ast

Inducers and inhibitors of P450 have corresponding effects on metabolism of montelukast

Block the effects of LTC4, LTD4, and LTE4

Blocks infiltration of inflammatory cells & prevents bronchoconstriction

Drug interactions:

Hepatitis

Drug interactions

(a) Monitor liver function

Inhibits P450 ↑ warfarin, propranolol, and theophylline concentrations

CONTRAINDICATED in patients with liver disease or ↑ liver

enzymes

Upset stomach

B R O N C H O D I L A T O R S

β2 - AGONISTS Albuterol Activation of β2 Salmeterol receptors  ↑ adenyly cyclase activity  ↑ intracellular cAMP levels  bronchodilation

Inhaled & oral Onset: 5–15min Peak: 0.5hrs Duration: 6hrs Inhaled Onset:30– 50min Peak:3hrs Duration: ≥12hrs

METHYLXANTHINES Theophyll Phosphodiesterase ine inhibition  ↑ cAMP Bronchodilation

Smooth muscle - relaxation; important in bronchi

CNS – stimulation

Tachycardia (high concentrations)

↓Peripheral vascular resistance

Anxiety, tremor, restlessness, tachycardia, and hypokalemia; more common with oral and parenteral administration

Regular use can lead to drug tolerance and an increase in exacerbations; corticosteroids enhance response to β2 agonists

Dose based on serum levels & patient response

Absorption: Rapidly and completely absorbed orally -Sustained-release preparations - ↓fluctuations between doses and ↑compliance

Inhaled for acute relief

Bronchodilator in asthma or COPD

Prevention of exercise-induced asthma

Emergency treatment (status asthmaticus) together with systemic glucocorticoids—Note: NOT salmeterol Preventive; NOT used for acute bronchospasm

TOXICITY: Mild symptoms do NOT always precede severe symptoms i. Mild - N, V, headache, nervousness, insomnia ii. Moderate - mild symptoms with sinus tachycardia & occasional PVCs iii. Severe - serious arrhythmias, seizures, death

Elimination -First order but at high concentrations - ZERO order

Aminophylline (theophylline ethylenediamine)

-Eliminated primarily by hepatic metabolism (90%)

Contains 85% theophylline–more soluble

Reversible airway obstruction due to asthma or other chronic lung disease

Factors affecting the half-life of theophylline

Rapid infusion of aminophylline  cardiac arrest and death

Diuretic actions - similar to thiazides

ii. Adenosine receptor blockade B R O N C H O D I L A T O R

ANITMUSCARINICS Ipratropium

Some elements of COPD are vagallymediated

does not cross BBB

&

Tiotropium

Treatment of Asthma & COPD

Adverse effects: Anitmuscarinics inhibit: bronchoconstriction, mucus hypersecretion  maintain brochodilation of Airway

Dry mouth and Sedation

Competitive antagonist of ACh for muscarinic receptors TREATMENT OF ASTHMA AND COPD LONG TERM CONTROL ASTHMA Steroids Modulators of Histamine Release Leukotriene Modifiers Theophylline M receptor Antagoints Long-acting B2 agonist Asthma treatment:

QUICK RELIEF ASTHMA Short-acting B2 agonist M receptor antagonist Steroids

STATUS ASTHMATICUS DOC: Corticoidsteroid & Bronchodilator  followed by Theophylline COPD

Step down treatment to minimize side effects, Step up treatment to achieve asthma control

ANTITUSSIVES OPIOIDS Codeine

Principles of treatment Decrease the sensitivity of cough center to incoming

stimuli

Acute and self-limited cough often does not require therapy

Adverse effects include CNS depression (manifested as drowsiness),

Prolonged cough can be a bothersome symptom that precipitates outpatient visits to the physician for treatment.

constipation, and potential for abuse NON-OPIOIDS Dextromethorphan

Diphenhydramine

Structurally related to codeine  its actually a synthetic derivative of codeine … szyrack is a Butthole

Identify a precipitant or establish an etiology and then either eliminate the precipitant or treat the underlying cause.

As effective as codeine without GI or CNS effects at usual doses

Nonspecific cough suppressive therapy may be useful when the cause of the cough cannot be identified or is not treatable. These drugs do not treat the underlying cause.

A first-generation antihistamine

Mechanism of action unclear DRUGS FOR CYSTIC FIBROSIS MUCOLYTIC Dornase α

Purulent airway secretions in patients with cystic fibrosis are due to polymerized DNA from degenerating leukocytes

Dornase α depolymerizes the DNA  ↓ viscosity of sputum

Minimal side effects: dyspnea, pharyngitis, rhinitis