Download Pharmacology II – Respiratory and Oxygenation

Pharmacology II – Respiratory
and Oxygenation
Kathy Plitnick RN PhD CCRN
Georgia Baptist College of Nursing
of Mercer University
Antitussives
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Suppress cough
Narcotics
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Non-Narcotics
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Codeine
Dextromethorphan
Use: dry, nonproductive cough
Dextromethorphan
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Available over-the-counter
Chemically related to opiates
Contraindicated in chronic cough
Caution in hepatic failure
Rare Side Effects
Interacts with other CNS depressants,
Amiodarone, Quinidine, Alcohol
Decongestants
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Relieve nasal obstruction
Adrenergic drugs
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Constrict arterioles, reduce blood flow
Mainly alpha receptors
Oral, topical (sprays & drops)
Use: relieve rhinitis, preop nasal surgery
Contraindicated: HTN, CAD, glaucoma
Sudafed (pseudoephedrine)
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Large doses: tachycardia, palpitations,
lightheadedness
Antihistamines
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Prevent effects of histamine
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Inhibit smooth muscle constriction
Decrease capillary permeablity
Decrease salivation
Use: allergic rhinitis, anaphylaxis, drug allergies,
transfusions, dermatologic, motion sickness,
sleep
Contraindicated: glaucoma, prostatic
hypertrophy, pregnancy, bladder obstruction
First Generation H1 Blockers
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Bind to central & peripheral H1 receptors
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CNS depression/stimulation
Anticholinergic effects
Interact with alcohol, CNS depressants
Safety precautions
Baseline assessment
Increase oral fluid intake
No driving
Diphenhydramine (Benadryl)
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High incidence of drowsiness
Short term management - insomnia
Topical, oral, IM, IV
Hypotension
Half-life 1-4 hours
Second Generation H1 Blockers
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Produce less sedation
Less CNS depression
Fexofenadine (Allegra)
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Rapid absorption
Half-life 14.4 hours
Caution in impaired renal function
Obtain thorough history of allergic reaction
Baseline pulmonary assessment
Administration with food
Safety measures
Expectorants
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Liquefy secretions
OTC preparations
Guaifenesin (Robitussin)
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Decreases adhesiveness, surface tension
Well absorbed
Symptomatic relief of cough
Do not use with persistent cough
Rare side effects
Assess type, severity of cough
Increase fluid intake, Humidity
Mucolytics
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Inhalation – liquefy mucus
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Nebulized, Direct instillation
Acetylcysteine (Mucomyst)
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Reduces viscosity
Acetaminophen overdose
Effective in 1 minute
Transient odor, irritated throat, N/V,
bronchospasm
Bronchodilators
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Adrenergic drugs that stimulate beta2
receptors, stimulate adenyl cyclase,
increase production of cAMP, produces
bronchodilation
Xanthines: Theophylline
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Inhibits phosphodiesterase
Inhibits pulmonary edema
Helps cilia clear mucus
Strengthens diaphragm
Theophylline
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Contraindicated: gastritis, PUD
Uses: asthma, bronchitis, emphysema
Aminophylline by continuous infusion
Administer with water, after meals
Monitor plasma levels: 10-20 mcg/ml
Avoid smoking
Signs of toxicity: anorexia, N/V, dizziness,
shakiness, restlessness, tachycardia,
hypotension, seizures
Beta Agonists – Albuterol
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Available oral, inhalation
Bronchodilation occurs 5-15 minutes
Stimulates smooth muscle receptors in
lungs, uterus, skeletal muscle
Side Effects: throat irritation, palpitations,
Tachycardia, hypertension, finger tremors
Always administer prior to antiinflammatory inhalers, steroids
Anticholinergics :
Ipratropium/Atrovent
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Block action of acetylcholine in bronchial
smooth muscle
Reduces GMP
Halts bronchoconstriction due to PNS
Administration by inhalation, intranasal
Ineffective in acute bronchospasm
Adverse Effects: cough, nervousness,
nausea, GI, headaches
Atrovent
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Do not use as an emergency agent
MDI’s – allow up to 1 minutes between
puffs
Rinse mouth after administration
Anti-inflammatory:
Glucocorticoids/Beclomethasone
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Increase number of beta receptors
Increase responsiveness of beta receptors
Produces smooth muscle relaxation
Inhalation: decrease inflammatory cells,
and swelling
Chronic asthma
Contraindicated: systemic fungal infections
Beclomethasone
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Caution: active infection, DM, PUD, HTN,
CHF, RI
Rinse mouth after administration
Teach proper inhalation technique
Use bronchodilators first
How Can You Avoid This
Medication Error?
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Mr. C, 66 years old, has worsening
COPD. At his last office visit, the MD
added ipratropium (Atrovent) and
beclomethasone (Vanceril) to his betaadrenergic (Alupent) inhaler. He visits
the office complaining of severe
dyspnea. You quickly grab his Atrovent
inhaler to administer a PRN dose and
try to get him to relax.
What drug error has occurred, and how
could this be avoided ??
Solution
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Acute dyspnea: only short-acting beta
adrenergic bronchodilators should be used
(Alupent)
Teach which inhaler to use in an emergency
When prescribed multiple inhalers, canister
should be a different color or marked in some
way
Know what the patient is prescribed
Mast Cell Stabilizers: Cromolyn
Sodium (Intal)
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No direct anti-inflammatory
Prevents release of mast cells after
exposure to allergens
Prophylactic mgmt severe asthma,
seasonal rhinitis
Available oral, inhalation, nasal spray,
ophthalmic
Cromolyn Sodium
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Use proper inhalation technique
Wait 10 minutes between doses
Rinse mouth after administration
Assess respiratory status
Leukotriene Receptor Antagonists:
Zafirlukast (Accolate)
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Binds to leukotriene receptors
Inhibits bronchoconstriction
Reduces airway edema, smooth muscle
constriction
Rapidly absorbed
Half-life 10 hours
Chronic treatment
Zafirlukast (Accolate)
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Aspirin increases concentration
Warfarin increases PT
Monitor SGPT
Side effects: headache, diarrhea, gastritis
Baseline LFT’s
Assess respiratory function
Increase fluid intake
Not for acute episodes
Take on empty stomach