Download Chapter 14 Antihistamines, Nasal Decongestants, Expectorants, and

Chapter 14
Antihistamines, Nasal
Decongestants,
Expectorants, and
Antitussives
Introduction
• Antihistamines and nasal decongestants are used to treat the
common cold and allergic rhinitis
• Nasal decongestants may also be used to treat sinusitis, middle ear
infections, and upper respiratory tract infections
• Symptoms of the common cold and allergic rhinitis are similar,
however their pathophysiology is quite different
S
Common Cold
• Caused by a viral infection
• Virus invades the respiratory tract
• Injures local cells
• Initiates inflammatory response in the affected area
• Leads to:
• Increase in blood flow to area
• Local edema
• Nasal discharge
• May lead to secondary bacterial infection and nasal congestion
S
Allergic Rhinitis
• Condition of an allergy-prone individual cause by an immunological
response from the contact of one or more environmental allergens
with the mucosal tissue
• Inflammatory response causes release of histamines and other
chemical agents
• Leads to:
• Increased secretion of mucus, congestion, and sneezing
• Redness and tear may result as a result of allergen particles entering the eye
S
Antihistamines
• Role of Histamine in the Body
• Released in the body as a response to tissue damage and the presence of
microorganisms and allergens invading body tissue
• Dilates arterioles
• Allows for increased blood supply to capillaries
• Leads to arterioles becoming red and large amounts of fluids leak into the interstitial
tisssues
• Inflammatory response allows for leukocytes to enter the area
S
Antihistamines(cont.)
• Do not affect the release of histamines
• Action: block the action of histamine at the H1 histamine receptor sites
• Most useful in the treatment of rhinitis
• Some may exert a local anesthetic action
• Effective in preventing or countering motion sickness, nausea, or vomiting
• May exert multiple effects:
• CNS Depressant activity
• Anticholinergic activity
• Varying degrees of sedation when combines with other depressant drugs or alcohol beverages
S
Caution with Antihistamines
• Anticholinergics
• Respiratory Disorders
• Nursing mothers
• Older Adults (Over 60 years of age and older)
S
Antihistamine Drugs
• Promethazine
• Contraindicated in comatose clients and other state of CNS depression
• Avoid with clients with hepatic disorders and those sensitive to phenothiazine drug
• Desloratadine (Clarinex)
• Nonsedating antihistamine, relief of nasal and other symptoms related to seasonal allergies, adverse effects: dry mouth and
pharyngitis
• Fexofenadine (Allegra)
• When combined with pseudoephedrine (Allegra-D), not recommended for person with hypertension, diabetes, ischemic heart disease,
glaucoma, hyperthyroidism, renal impairment, or prostate cancer
• Cetirizine
• Active metabolite of hydroxyzine, does not cause drowsiness
• Levocetirizine dihydrochloride (Xyzal)
• Oral antihistamine for allergic rhinitis and urticaria
• Approved for adults and children 6 years and older
• Excreted in urine and should be cautiously use in clients with renal impartment
• Contraindicated in adults with end-stage renal disease (ESRD) and children 6-12 with renal impairment
• Olopatadine hydrochloride (Patanase), azelastine (Astepro)
Antihistamine Drugs
• Commonly used for symptoms of Allergies
• Block peripheral H1 histamine receptors than those in the CNS
• Results in lower incidence of sedation
S
Nursing implications
for Antihistamines
• Encourage the client to read the directions for use and warnings on OTC products and to
follow instructions
• Clients with hypertension should have their blood pressure monitored with the adverse
effect of further increasing blood pressure
• Antihistamine agents can cause increased intraocular pressure worsening glaucoma
• Can cause urinary retention worsening prostatic hypertrophy
• Emergency supplies should be on hand for nurse
• Ex: epinephrine, Benadryl, corticosteroids
• Referral to health care provider for possible desensitization
• Try to determine offending allergen, suggest ways to minimize contact
S
Question
Name four instances in which you should caution using antihistamines?
S
Expectorants pg 464
• Aid in the expectoration of mucus
• Reduces the viscosity of secretions
• Stimulates the flow of respiratory secretions
Q
Secretions
• Thinning and loosening of endobronchial mucus
and phlegm to be expelled by cough
1. Teach to cough productively by sitting in upright
position & taking slow, deep breaths first
2. Encourage fluids to help liquefy secretions
• Increased secretion activity in the respiratory tract
aids in hydrating dry, irritated tissue
Q
Expectorants
• Iodides-potassium iodide (saturated solution of potassium
iodide)-used because of their ability to increase secretions of
respiratory tract fluids
• Metallic taste, fever, anorexia and limited use because of
possible hypersensitvity
Q
Decongestants
pg 452
Nasal Decongestants constrict dilated blood vessels in the nasal mucosa by
stimulating alpha-adrenergic nerve receptors in vascular smooth muscle
• Reduces flow of blood in edematous area
• Slows the formation of mucous; permits better drainage
Most common medication forms of decongestants
Nasal inhalation
Oral
A
Common Problems
pg452
Rebound congestion, return of excessive tissue fluid occurring as a result of use for an extended time
and dosing beyond recommendation by manufacturer
Excessive use causes local Ischemia along with Irritation of the Nasal mucosa; that leads to extensive
secondary vasodilation and congestion
Adverse effects such as elevation of blood pressure and CNS stimulation, may occur if decongestant
solutions drains through nasal passage and swallowed by the client
A
Nasal inhalants
pg458-459
(ex. Afrin, Duration, Adrenalin Chloride)
Inhalers are generally plastic containers containing an inert fibrous material
impregnated with a volatile decongestant drug
Container is open, inhaled through nostrils, vapor decongestant drug comes
in contact with nasal mucosa and produces decongestant action
A
Oral decongestants
pg458
(ex. Drixoral tablets, Sudafed)pg 460
Generally longer duration of action than that of the topical agents, BUT effect tends
to be less constrictive
May affect vascular beds other than those found in the nasal mucosa
May precipitate or aggravate High BP, cardias arrhythmias, ishemic HD, DM and
hyperthyroidism
A
Palliative Care
pg458
For the common cold and allergic rhinitis decongestants and antihistamines are NOT
curative
Cromolyn Sodium has proved to be effective in prevention/treatment of
allergic rhinitis, it inhibits histamine release and the release of other chemical agents
freed as a result of an allergic response by stabilizing mast cells; therefore reduce the
severity/ frequency of acute episodes of allergic rhinitis
A
Nursing Implications
pg470
• Teach clients the proper way to administer nasal sprays and nose drops
• Topical nasal decongestants should be given 20 mins before meals, so the nasal
passages will be clear for breathing during eating or sucking
• Hypertensive clients should monitor BP, when taking
Antihistamines/Decongestants with adverse effect increasing BP
• Children under 6 Do not take epinephrine HCl
A
Question
What is the cause of rebound congestion?
A
Intranasal Steroids
pg458
(ex. Beclomethasone dipropionate (Beconase), mometasone (Nasonex), fluticanose
propionate (Flonase)
• Local corticosteroids used in conjunction with antihistamines and decongestants to
address congestion and associated with allergies
• Applied nasally, but rather than a spray, administered as vapors
• Intranasal steroids also are used adjunct therapy for clients with asthma
• Unlike, nasal decongestants, I.S. administration does not produce immediate
effects, regular use is required, for full therapeutic benefits from these products
K
Intranasal Steroids (cont.)
pg458,464
• Ciclesonide, 7th newest nasal corticosteroid, indicated in the treatment of nasal
symptoms of seasonal rhinitis in adults and children 6 years of age and older and
nasal symptoms of perennial allergic rhinitis in adults and children 12 years of age
and older
• When symptoms of seasonal or perennial rhinitis do not respond well to
conventional forms of therapy, intranasal corticosteroid administration may be
advisable
• Use of saline nose drops has proved to be successful for those clients taking other
decongestants and those just using the saline drop for nasal congestion; advantage
is it is not habit- forming, can be used more often and are less expensive
K
Expectorants
• Iodides-potassium iodide (saturated solution of potassium
iodide)-used because of their ability to increase secretions of
respiratory tract fluids
• Metallic taste, fever, anorexia and limited use because of
possible hypersensitvity
Q
Antitussives
• Agent that prevents or relieves coughs
• Coughs
• Physiological mechanism useful in removing foreign material and excessive
secretions from the respiratory tract
• May be productive OR nonproductive
• Involuntary coughs should not be suppressed unless they cause respiratory
discomfort or does not facilitate removal of excess secretions from the
respiratory tract
S
Major Drawbacks of Antitussives
• May cause independence, bronchial constriction, CNS depression,
and constipation
• Use Cautiously In Clients with:
• Preexisting Pulmonary distress
• Older Adults
• Children
• Clients using most Psychotropic Agents
• Clients using Sedative Hypnotics
• Clients using Alcohol
• Clients using other CNS Depressants
S
Antitussive Drugs
• Codeine and hydrocodone
• Considered to be the most effective and reasonably safe
• Direct depressant effect on the medulla of the brain depressing the cough reflex
• Ex: guaifenesin and codeine (Robitussin A-C)
• Expectorant combined with Antitussive
• Used for temporary relief of cough due to throat irritation
• Irritation can lead to a more serious condition
• Ex: bronchitis
S
Antitussive Drugs
• dextromethorphan HBr
• Chemical derivative of the opiate antitussives
• Direct depressant effect on the medulla of the brain depressing the cough reflex
• Does NOT cause CNS depression, analgesia, or dependence
• Dextromehorphan is used in most nonprescription cough syrups
• Intended for Adults and Children over 4 years old
• Ex: Robitussin DM and Benylin DM
S
Antitussive Drugs
• Benxonatate (Tessalon)
• Derivative of procaine
• Acts peripherally by providing local anesthetic action, impairs sensation of the
stretch receptors located in the respiratory tract, lungs, and pleura, thereby
interfering with the cough reflex
• Does NOT impair respiration or have an analgesic effect
• Acts within 15-20 minutes with duration of effects lasting 3-8 hours
S
Antitussive Drugs
• Diphenhydramine HCl (Benadryl)
• Potent antihistamine
• Anticholinergic properties
• Must be used with caution in clients with:
• Glaucoma
• Prostatic hypertrophy
• Obstructive pulmonary diseases
• When used with alcohol or other CNS depressants, excessive sedation may occur
• Client should be made aware of possible impairment of physical or mental
capabilities, or both while taking the drug
S
Nursing Implications
• Antitussives are commonly used in the form of syrups
• Monitor for therapeutic and untoward effects, sensitivity to any drugs, and drug
interactions
• Administering Antitussives:
• Syrup should be give last when its purpose is for a soothing effect
• Should NOT be immediately followed by water or other liquids or foods
• Must be kept out of reach of children, may be potential for accidental poisoning due to the
pleasant flavoring
• Promote comfort in persons with chronic coughs
• Environmental irritants should be controlled or avoided as much as possible
• Assure high fluid intake 2,000-2,500 mL/day to keep secretions liquid
• Assess for overhydration (most common in adults and small children)
S
Question
A client receiving an antitussive with hydrocodone should be
monitored for:
a. Constipation
b. Cholinergic effects
c. Diarrhea
d. Urinary frequency