Week 6 ~ Respiratory System Flashcards
What type of treatment is used for Upper Respiratory Diseases?
Empirical therapy —> because it’s difficult to identify between viral and bacterial causes of the common cold
What are the 4 upper respiratory disease (URI) drugs used for?
The common cold
Mostly caused by a virus
The virus invades tissues of the URT and an inflammatory response occurs, resulting in mucus production
How do Antihistamines work?
Drugs that directly compete with histamine for specific receptor sites
2 Histamine Receptors?
- H1 (Histamine 1) –> Commonly referred to as Antihistamines
- H2 (Histamine 2) –> Reduce gastric acid in peptic ulcer disease
- -> Include Cimetidine, Ranitidine
What are the 3 properties of Antihistamines?
- Antihistamine
- Anticholinergic
- Sedative
Antihistamines Mechanism of Action
Block action of histamine at the H1 Receptor sites by competing with histamine
Should be given early before histamine binds to receptors
Drying effect reduces nasal, salivary and lacrimal gland production
Sedative effect may cause drowsiness
What symptoms does antihistamines prevent that are caused by histamine?
- Vasodilation
- Increased GI and respiratory secretions
- Increased capillary permeability and itching
Antihistamines Indications
Nasal allergies/Allergic Reactions
Motion Sickness
Sleep Disorders
Parkinson’s Disease
Seasonal Allergies, ie hay fever
Antihistamines Contraindications
Known drug allergy
Children
Acute asthma
Heart Disease
Narrow angle glaucoma
Hypertension
Kidney Disease
Antihistamines Adverse Effects
Anticholinergic effects such as dry mouth, difficulty urinating, constipation, drowsiness, changes in vision
Antihistamines Drug Interactions
Alcohol
MOI’s
CNS Depressants…may increase CNS depressant effects
Apple/Grapefruit/Orange Juice
St Johns Wort
2 Types of Antihistamines
- Traditional: work peripherally and centrally
—>have Anticholinergic effects, more effective
Then no sedating drugs - Nonsedating: work peripherally
- –> eliminate unwanted adverse effects, longer duration
2 Kinds of Traditional Antihistamine Drugs?
- Diphenhydramine
2. Chlorpheniramine
3 Kinds of Non-Sedating Antihistamine Drugs
- Fexofenadine —> Allegra
- Loratadine –> Claritin
- Cetirizine —> Reactin
3 Types of Decongestants
- Adrenergics –> Sympathomimetics
- Anticholinergics –> Parasympatholytics
- Corticosteroids —> Intranasal Steroid
(Topical)
What’s the largest group of Decongestant?
Adrenergics
2 methods of administering decongestants?
- Oral
2. Inhaled/topically applied to nasal membranes
Oral Decongestants
Delayed onset but prolonged effects
No rebound congestion
Effect is less potent than topical decongestants
Name of an Oral Decongestant?
Pseudo ephedrine
Topical Nasal Decongestants
Prompt onset and produces potent effect
Causes rebound congestion, making the condition worse if used for several days
3 Types of Topical Nasal Decongestants
- Topical Adrenergics
- Intranasal Adrenergic (Inhaled)
- Intranasal Steroids
3 Intranasal Adrenergic Drugs
- Oxymetazoline Hydrochloride —> Vicks, Claritin
- Phenylephrine Hydrochloride
- Xylometazoline Hydrochloride –> Otrivin
3 Intranasal Steroid Drugs
- Beclomethasone Dipropionate
- Fluticasone Proprionate
- Flunisolide
Nasal Decongestant ADRENERGICS Mechanism of Action
Act on blood vessels surrounding nasal sinuses
Constrict small blood vessels that supply upper respiratory tract
RESULTS: tissues shrink, nasal secretions in swollen mucous membranes are able to drain and nasal stuffiness is relieved
Nasal Decongestion NASAL STEROIDS Mechanism of Action
Shrink engorged nasal mucous membranes
Relieve nasal stuffiness by acting on blood vessels surround nasal sinuses, have an anti inflammatory effect, decrease immune cells that respond to the inflammatory response
Nasal Decongestant Contraindications
Drug Allergy
Narrow angle glaucoma
Diabetes
Hypertension
Prostatitis
Hyperthyroidism
Uncontrolled Cardiovascular disease
Nasal Decongestants should be used cautiously in patients with history of what?
- Stroke/TIA’s
- Diabetes
- Long Standing Asthma
- Benign Prostatic Hyperplasia
- Cerebral Arteriosclerosis
Decongestant Adverse Effects
- ADRENERGICS: causes nervousness, insomnia, tremors, palpitations
- STEROID: causes local mucosal dryness
4 Drugs for Upper Respiratory Disease
- Antihistamines
- Decongestants
- Antitussives
- Expectorants
2 Types of Cough
- Productive: cough up phlegm etc
2. Nonproductive: dry cough
What are Antitussives?
Drugs used to stop or reduce coughing
May be opiod or nonopiod
Used only for Non-productive coughs
Opiods Mechanism of Action as an Antitussives?
Suppress the cough reflex in the medulla
Types of Antitussive Opiods
Codeine –> Robitussin, Dimetane - C, Dimetapp - C
Hydrocondone
Antitussive Nonopiod Mechanism of Action
Suppress the cough reflex by numbing the stretch receptors of the respiratory tract and preventing the cough reflex from being stimulated
Types of Nonopiod Antitussives?
Dextromethorphan –> Benylin DM-E, Buckleys, Robitussin
Vick’s
Antitussive Contraindications
Drug allergy
Opioid Dependancy
High risk respiratory depression
Antitussive Opioid Adverse Effects
Sedation
Nausea/Vomiting
Lightheadedness
Constipation
Antitussive Nonopioid Adverse Effects
Dizziness
Drowsiness
Nausea
What are Expectorants?
Drugs that aid in the expectoration of mucus
Expectorant Mechanism of Action
- Reflex Stimulation –> Loosens/thins secretions in respiratory
Tract creating mucus that’s easier to remove*Gauifenesin (Robitussin)
- Direct Stimulation –> Secretory glands are stimulated to produce
More respiratory tract fluids
*Iodine containing products: Iodinated Glycerol Potassium Iodide (less used)
Expectorant Indications
Used for relief of productive coughs associated with common cold, bronchitis, pertussis, laryngitis, sinusitis, pharyngitis
Expectorant Contraindications
Drug allergy
Hyperkalemia (for potassium containing expectorants)
Expectorant Adverse Effects
Nausea
Vomiting
Gastric Irritation
Diseases of Lower Respiratory Tract?
COPD
Asthma
Emphysema
Chronic Bronchitis
2 Types of Respiratory Drugs
- Bronchodilators
2. Non-Bronchodilators
2 Bronchodilators
B-Adrenergic Agonists
Xanethine Derivatives
2 Non Bronchodilators
Antileukotrines
Corticosteroids
What do B-Agonists do?
Stimulate B2 Adrenergic Receptors which are located throughout the lungs
3 Types of B-Agonists
- Non-Selective Adrenergics
- Non - Selective B-Adrenergics
- Selective B2 Drugs
What do Non-Selective Adrenergics do?
Stimulate A1, B1 (Cardiac), B2 (Respiratory) receptors
*Include Epinephrine (Adrenaline)
What do Non-Selective B-Adrenergics do?
Stimulate both B1 and B2 Receptors
*Isoproterenol
What do Selective B2 drugs do?
Stimulate only B2 receptors
*Salbutamol
B-Agonists Mechanism of Action
Specific receptors are stimulated and cause dilation of the airways resulting in:
Activation of B2 receptors –> Activates cAMP –> Relaxes smooth muscles of the airway –> bronchial dilation = Increased air flow
B Agonists Indications
~ Bronchopasm related to asthma, bronchitis
~ Treat and prevent acute attacks
~ Treatment of hypotension and shock
~ Cause uterine relaxation to prevent premature labour
~Treat Hyperkalemia –> stimulates K+ to shift into cells
B-Agonist Adverse Effects
Anorexia Insomnia Restlessness Tremors Cardiac Stimulation Hyperglycaemia
B-Agonist Contraindications
Drug Allergy
Uncontrolled cardiac dysrhthmias
High risk of stroke
B-Agonist Drug Interactions
Increase risk of hypertension
Increase risk of cardiac toxicity
Require an adjustment to Antihyperglycemic drugs
2 Synthetic types of Xanthines?
- Aminophylline
2. Oxtriphylline
What’s the only Xanthines Derivative used as a Bronchodilator?
Theophylline
What are 3 Natural Plant Alkaloid Xanthines?
- Caffeine
- Theobromine
- Theophylline
Xanthines Derivative Mechanism of Action
- Increase levels of energy producing cAMP by competitively inhibiting Phosphodiesterase, the enzyme that breaks down cAMP —-> decreased cAMP levels —> smooth muscle relaxation
- -> Bronchodilation –> increased airflow - Stimulate CNS and Cardiovascular System (Increase heart rate)
- Diuresis
What is the category of Xanthines Derivatives?
Bronchodilators
Xanthine Derivative Indications
Asthma
COPD
Emphysema
Chronic Bronchitis
Xanthine Derivative Contraindications?
Drug allergy Peptic Ulcers Seizure disorders Hyperthyroid Uncontrolled cardiac Dysrhthmias
Xanthines Derivative Adverse Effects
Nausea/Vomiting Anorexia Increased urination Gastroesophogeal Reflux during sleep Sinus tachycardia Palpitations Extra systole Ventricular Dysrhythmias
Xanthine Derivative Drug Interactions
When used with Sympathomimetics (caffeine) increased heart and CNS stimulation result
St Johns Wort (Hypericum Perforatum) and smoking enhance the rate of Xanthine drug metabolism
Anticholinergics Mechanism of Action
Bind to ACh receptors, preventing ACh from binding —> prevents bronchi constriction = dilation of airways
Types of Anticholinergic Drugs
- Ipratropium Bromide (Atrovent)
- Tiotropium
* Slow and prolonged action*
Anticholinergic Adverse Effects
Dry mouth or throat Anxiety Headache Cough Nasal Congestion Palpitations GI distress
What are Antileukotriene Drugs?
*New class of asthma medication
Prevent Leukotrienes from attaching to receptors on circulating immune cells and immune cells within the lungs = inflammation in the lungs is blocked
2 Types of Antileukotriene Drugs?
- Montelukast - Singulair
- Zafirlukast - Accolate
* Leukotriene receptor antagonists*
What do Leukotrienes do?
Are substances released when a trigger such as dust starts a series of chemical reactions in the body.
They cause inflammation, mucus production, broncho constrictions, coughing, sneezing, SOB
Antileukotriene Drug Effects
By blocking Leukotrienes they:
1. Prevent smooth mm contraction of bronchial airways
2. Decrease mucus secretion
3. Prevent vascular permeability
4. Decrease neutrophil and leukocytes in the lungs, preventing
Inflammation
Antileukotriene Indications
Used for the prophylaxis and long term treatment of asthma in adults or children above age 12
Antileukotriene Contraindications
Drug allergy
Allergy to povidone, lactose, titanium dioxide, cellulose derivatives
Antileukotriene Adverse Effects
Headache
Nausea
Diarrhea
Liver Dysfunction
Corticosteroids Mechanism of Action
Used for Chronic Asthma
~Available in oral and inhaled forms
Anti-Inflammatory Effects
Stabilize membranes of cells (WBC/Leukocytes) that release harmful broncho constricting substances
Increase responsiveness of bronchial smooth muscle to B-Adrenergic stimulation
What symptoms does Corticosteroids not relieve?
Symptoms of Acute Asthma Attacks
4 Inhaled Corticosteroid Drugs?
- Beclomethasone Dipropionate
- Budesonide
- Fluticasone Furoate
- Fluticasone Propionate - Flonase, Flovent, Diskus
Inhaled Corticosteroid Indications
Bronchospastic Disorders that aren’t under control by conventional bronchodilators
NOT for acute asthma!!
Inhaled Corticosteroid Contraindications
Candida/Fungal Infections
Hypersensitive to Glucocorticoids
Inhaled Corticosteroid Adverse Effects
Coughing
Dry mouth
Pharyngeal Irritation
Oral Fungal Infections
Systemic effects are rare because it’s an inhalation therapy