Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharmocology RN212 > Chap 36 Antihistamines, Decongestants, Antitussives, and Expectortants > Flashcards

Chap 36 Antihistamines, Decongestants, Antitussives, and Expectortants Flashcards

1
Q

Understanding the Common Cold






A

Most caused by viral infections** (rhinovirus or influenza virus

Virus invades tissues (mucosa) of upper respiratory tract, causing upper respiratory infection (URI)**

Mucosal irritation also causes release of several inflammatory and vasoactive substances, dilating** small blood vessels in the nasal sinuses and causing nasal congestion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Treatment of the Common Cold

A

Involves combined use of *antihistamines, nasal decongestants, antitussives, and expectorants**
Treatment is symptomatic** only, not curative.
Symptomatic treatment does not eliminate the causative pathogen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Histamine

A

Major inflammatory mediator in many allergic disorders
Allergic rhinitis* (e.g., hay fever and mold, dust allergies)
Anaphylaxis*
Angioedema*
Drug fevers
Insect bite reactions*
Urticaria (itching)*

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Histamine Effects

A

Nerve impulse transmission in the central nervous system

Constriction/Contraction** of the smooth muscle

Increased heart rate**

Increased in body secretions**( Gastric secretions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Antihistamines

A

Drugs that directly compete* with histamine for specific receptor sites

Two histamine receptors**
H1 (histamine 1)*
H2 (histamine 2)*

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Antihistamines: Mechanism of Action

A

Block action of histamine at H1 receptor sites**

Compete with histamine for binding at unoccupied receptors**

Cannot push histamine off the receptor if already bound**

H1 blockers TREAT ALLERGIC REACTIONS**

Should be given early** in treatment before all the histamine binds to the receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Antihistamines and Histamine Antagonists

A

H1 antagonists (also called H1 blockers) **
Examples: chlorpheniramine, fexofenadine (Allegra), loratadine* (Claritin), cetirizine* (Zyrtec), diphenhydramine* (Benadryl)

Antihistamines have several properties
Antihistaminic*
Anticholinergic*
Sedative*

H2 blockers or H2 antagonists**
Used to reduce gastric acid in peptic ulcer disease
Examples: cimetidine (Tagamet), ranitidine (Zantac), famotidine* (Pepcid), nizatidine (Axid)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Different Generations of histamines

A

1st gen
Diphenhydramin
hydroxyzine
promethazine

2nd gen
loratadine
cetirizine
azelastine

3rd gen
desloratadine
fexofenadine
levocetirizine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Histamine Vs Antihistamine Effects

A

Cardiovascular ***
Hista
Dilates blood vessels
Increased blood vessel permeability
Anti
Reduces dilation and blood vessel permeability

Immune***
Hista
Works on mast cells
Allergic reactions
Anti
Binds to Histamine receptors.
Prevents histamine response

Smooth Muscle***
And glands
Hista
Increase in secretions
Anti
Reduces Secretions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Antihistamines: Two Types

A

Traditional*
: brompheniramine, chlorpheniramine, dimenhydrinate, diphenhydramine, meclizine, and promethazine*

Nonsedating*
: loratadine, cetirizine, and fexofenadine***

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Traditional Antihistamines

A

Older
Work both peripherally and centrally**
Have anticholinergic effects, making them more effective than nonsedating drugs in some cases
Examples: diphenhydramine (Benadryl), brompheniramine, chlorpheniramine, dimenhydrinate, meclizine, promethazine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Nonsedating/Peripherally** Acting Antihistamines

A

Developed to eliminate unwanted adverse effects,** mainly sedation
Work peripherally to block** the actions of histamine; thus, fewer central nervous system (CNS)* adverse effects*
Longer duration of action (increases compliance)
Examples: fexofenadine (Allegra),
 loratadine (Claritin), cetirizine (Zyrtec)***

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Antihistamines: Indications*

A

Management of:
Nasal allergies
relieve symptoms associated with the common cold* ( sneezing, runny nose)
Seasonal or perennial allergic rhinitis** (hay fever)
Allergic reactions**
Motion sickness
Parkinson’s disease
Sleep disorders

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Antihistamines: Contraindications

A

Known drug allergy
Narrow-angle glaucoma**
Cardiac disease, hypertension*
Kidney disease
Bronchial asthma, chronic obstructive pulmonary disease (COPD)
Sole drug therapy during acute asthmatic attacks

Peptic ulcer* disease
Seizure disorders
Benign prostatic hyperplasia (BPH)**
Pregnancy*
* Antihistamines drug therapy should be discontinued 4 days prior to allergy testing***

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Antihistamines: Adverse Effects

A

Anticholinergic (drying) effects: most common
Dry mouth*
Difficulty urinating*
Constipation*
Changes in vision*

Drowsiness
Mild drowsiness* to deep sleep

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Antihistamines:Nursing Implications

A

Gather data about the condition or allergic reaction that required treatment; also assess for drug allergies.

Contraindicated in the presence of acute asthma attacks and lower respiratory diseases, such as pneumonia

Use with caution in patients with increased intraocular pressure, cardiac or renal disease, hypertension, asthma, COPD, peptic ulcer disease, BPH, or pregnancy.

Instruct patients to report excessive sedation, confusion, or hypotension.

Instruct patients to avoid driving** or operating heavy machinery; advise against consuming alcohol or other CNS depressants.

Instruct patients not to take these medications with other prescribed or OTC medications without checking with their prescribers.

Best tolerated when taken with meals**; reduces GI upset

If dry mouth occurs, teach patients to perform frequent mouth care, chew gum, or suck on hard candy** (preferably sugarless) to ease discomfort.

Monitor for intended therapeutic* effects.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Nasal Congestion

A

Excessive nasal secretions
Inflamed and swollen nasal mucosa**
Primary causes
Allergies*
URIs (common cold)*

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Decongestants*: Types

A

Three main types are used:
Adrenergics*
Largest group
Sympathomimetics
Anticholinergics*
Less commonly used
Parasympatholytics
Corticosteroids*
Topical, intranasal steroids

Two dosage forms
Oral*
Inhaled or topically** applied to the nasal membranes

18
Q

Nasal Decongestants : Indications

A

Relief of nasal congestion associated with:
Acute or chronic rhinitis*
Common cold*
Sinusitis*
Hay fever
Other allergies

May also be used to reduce swelling** of the nasal passage and facilitate visualization of the nasal or pharyngeal membranes before surgery or diagnostic procedures

19
Q

Nasal Decongestants: Mechanism of Action

A

Site of action: blood vessels surrounding nasal sinuses**

Adrenergics
Constrict small blood vessels** that supply upper respiratory tract structures
As a result, these tissues shrink, and nasal secretions in the swollen mucous membranes are better able to drain.

Nasal steroids*
Anti-inflammatory effect**
Work to turn off the immune system cells** involved in the inflammatory response
Decreased inflammation results in decreased congestion.

20
Q

Topical Nasal Decongestants

A

Adrenergics
Ephedrine, oxymetazoline (Afrin)
Intranasal steroids*
Beclomethasone* dipropionate (Beconase), budesonide(Rhinocort), flunisolide (Nasalide), fluticasone (Flonase), triamcinolone* (Nasacort), ciclesonide (Omnaris)
Intranasal anticholinergic*
Ipratropium* (Atrovent)

Topical adrenergics
Prompt onset
Potent
Sustained use over several days causes rebound congestion, making the condition worse.
Ephedrine, oxymetazoline, phenylephrine, and tetrahydrozoline

21
Q

Oral Decongestants

A

Prolonged decongestant effects but delayed onset
Effect less potent than topical
No rebound congestion**
Exclusively adrenergics
Example: pseudoephedrine (Sudafed)

22
Q

Inhaled Intranasal Steroids and Anticholinergic Drugs*

A

Not associated with rebound congestion**

Often used prophylactically* to prevent nasal congestion in patients with chronic upper respiratory tract symptoms

23
Q

Nasal decongestants

A

Vasodilation** of nasal blood vessel

use nasal decongestant**

vasoconstriction** of nasal blood vessels

24
Q

Nasal Decongestants: Contraindications

A

Drug allergy
Narrow-angle glaucoma*
Uncontrolled cardiovascular disease, hypertension*
Diabetes and hyperthyroidism
History of cerebrovascular accident or transient ischemic attacks
Long-standing asthma*
BPH*
Diabetes

25
Q

Nasal Decongestants: Adverse Effects

A

Adrenergics Steroids
Nervousness Local mucosal dryness
Insomnia and irritation
Palpitations
Tremors
(Systemic effects caused by
adrenergic stimulation of the
heart, blood vessels, and CNS)

26
Q

Nasal Decongestants:Interactions

A

Systemic sympathomimetic drugs and sympathomimetic nasal decongestants are likely to cause drug toxicity when given together.
Monoamine oxidase inhibitors(MAOI)( and sympathomimetic nasal decongestants raise blood pressure.
Methyldopa
Urinary acidifiers and alkalinizers

27
Q

Two Basic Types of Cough

A

Productive cough:*
congested; removes excessive secretions

Nonproductive cough*
: dry cough

28
Q

Antitussives, Expectorants, and Mucolytics

A

Antitussive*
used to prevent or relieve a cough*

Expectorant*
promotes secretion of sputum by the air passages, used to treat coughs**

Mucolytic*
acts to break down thick mucus*

29
Q

Antitussives

A

Drugs used to stop or reduce coughing**

Opioid and nonopioid

Used only for nonproductive coughs!

May be used in cases when coughing is harmful

30
Q

Antitussives: Mechanism of Action

A

Opioids*
Suppress the cough** reflex by direct action on the cough center in the medulla**
Analgesia, drying effect on the mucosa of the respiratory tract, increased viscosity of respiratory secretions, reduction of runny nose and postnasal drip
Examples
Codeine*
Hydrocodone*

Nonopioids
Dextromethorphan: works in the same way**
Not an opioid
No analgesic properties
No CNS depression
Benzonatate*: Suppressing the cough receptors
Suppress the cough reflex by numbing the stretch receptors in the respiratory tract and prevent reflex stimulation of the medullary cough center

31
Q

Antitussives: Indications*

A

Used to stop* the cough reflex when the cough is nonproductive* or harmful

32
Q

Antitussives: Adverse Effects

A

Benzonatate*
Dizziness, headache, sedation, nausea, and others

Dextromethorphan*
Dizziness, drowsiness, nausea

Opioids*
Sedation*, nausea, vomiting, lightheadedness, constipation

33
Q

Antitussives:Nursing Implications*

A

Perform respiratory and cough assessment and assess for allergies.

Instruct patients to *avoid driving or operating heavy equipment because of possible sedation, drowsiness, or dizziness.**

34
Q

Antitussives:Nursing Implications

A

Report any of the following symptoms to the caregiver:
Cough that lasts more than 1 week
Persistent headache
Fever
Rash

Antitussive drugs are for nonproductive coughs.

Monitor for intended therapeutic effects.

35
Q

Expectorants

A

Drugs that aid in the expectoration (removal) of mucus**

Reduce the viscosity of secretions**

Disintegrate and thin secretions**

Example: guaifenesin*

36
Q

Expectorants: 
Mechanisms of Action*

A

Reflex stimulation
Drug causes irritation of the GI tract.
Loosening and thinning of respiratory tract secretions occur in response to this irritation.

Direct stimulation**
The secretory glands are stimulated directly to increase their production of respiratory tract fluids.

Final result: thinner mucus that is easier to remove

37
Q

Expectorants: Drug Effects*

A

By loosening and thinning sputum** and bronchial secretions**, the tendency to cough is indirectly diminished.

38
Q

Expectorants: Indications*

A

Used for the relief of productive coughs associated with:
Common cold
Bronchitis
Laryngitis
Pharyngitis
Coughs caused by chronic paranasal sinusitis
Pertussis
Influenza
Measles

39
Q

Expectorants: Nursing Implications*

A

Patients taking expectorants should receive *more fluids, if permitted, to help loosen and liquefy secretions.**

Report a fever, cough, or other symptoms lasting longer than 1 week.

Monitor for intended therapeutic effects.

40
Q

Supplements and Herbal Products*

A

Vitamin C*

Echinacea*

Goldenseal

41
Q

Herbal Products: Echinacea*

A

Reduces symptoms* of the common cold* and recovery time

Adverse effects
Dermatitis
GI disturbance
Dizziness
Headache

42
Q

Anaphylaxis:* Severe Allergic Reactions

A

Release of excessive* amounts of histamine* can lead to:
Constriction* of smooth muscle, especially in the stomach and lungs
Increase in body secretions
Vasodilatation and increased capillary permeability, movement of fluid out of the blood vessels and into the tissues, and drop in blood pressure and edema

LOW BLOOD PRESSURE*

TREATMENT*
injection of epinephrine(adrenaline) right away**

Pharmocology RN212 (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions