chapter 36, Antihistamines... Flashcards
A drug that directly compete with histamine for specific receptor sites?
Antihistamines
Antihistamines are most beneficial in management of?
nasal allergies seasonal or perennial allergic rhinitis (eg., hay fever) typical symptoms of the common cold allergic reactions motion sickness Parkinson's disease vertigo sleep aid
H1 antagonist include drugs such as?
diphenhydramine chlorpheniramine fexofenadine loratadine cetirizine
H1 antagonists are of greatest value in the Tx of?
nasal allergies, particularly seasonal hay fever.
to relieve the symptoms of the common cold, such as sneezing, and runny nose (palliative)
When H1 antagonist are given to relieve the symptoms of the common cold, such as sneezing and runny nose. They are acting as?
Palliative (they can help alleviate the symptoms of a cold but can do nothing to destroy the virus causing it).
what are the primary anticholinergic actions of antihistamines?
they affect the secretions of the lacrimal, salivary, and respiratory mucosal glands.
Antihistamines should not be used as the sole drug therapy during acute asthmatic attacks. True or false?
True
What are some contraindications for antihistamines?
acute asthmatic attacks narrow-angle glaucoma cardiac disease, kidney disease hypertension bronchial asthma, COPD peptic ulcer seizure disorders benign prostatic hyperplasia pregnancy.
The herbal therapy Echinacea is contraindicated for patient with?
HIV, TB, connective tissue disease and multiple sclerosis (MS)
Antihistamine effects may be potentiated excessively by interaction with?
apple
grapefruit
orange juice
St. John’s wort
How long should an antihistamine be discontinued prior to allergy testing?
at least 4 days
excessive use of decongestants whether oral forms or nasal inhaled forms may lead?
rebound congestion
what happens when a patient has rebound congestion?
The nasal passages become more congested as the effects of the drug wear off. Patient generally uses more of the drug, precipitating a vicious cycle with more congestion.
patient taking expectorants should not use these medication for how long?
longer than 1 week
when is coughing not useful and may even be harmful
after surgical procedure such as hernia repair or in cases of nonproductive or dry cough
patients with upper or lower respiratory symptoms or disease processes should avoid?
dry air, smoke-filled environments and allergens
patients taking expectorants should avoid
alcohol and products containing alcohol
what should the nurse assess for before administering the traditional antihistamines such as diphenhydramine, chlorpheniramine, or brompheniramine
The nurse must ensure the patient has no allergies to this group of medications, even though these drugs are used for allergic reactions.
why should traditional antihistamines not be used when patients are experiencing an acute asthma attack and those with lower respiratory tract disease or at risk for pneumonia?
because the antihistamines dry up secretions; if the patient cannot expectorate the secretions, it may become viscous (thick), occlude airways,and lead to atelectasis or further infections or occlusion of the bronchioles.
assessments for patients taking antitussive
safety because most of these drugs results in sedation, dizziness, and drowsiness.
allergies.
Respiratory assessment (rate, rhythm and depth, breath sounds, presence of cough, ABGs.
assessments for the use of decongestants
BP and HR
what is recommended or prescribed for patients who have a cough and need to bring up secretions more easily?
expectorants
What should the nurse implement with patients who experience dry mouth.
encouraged to chew or suck on candy (sugar free), or OTC throat, cough, or cold lozenges or to chew gum.
perform frequent mouth care.
when assessing a patient who is receiving antihistamines, the nurse will recognize that some potential contraindications are?
narrow-angle glaucoma cardiac disease kidney disease hypertension bronchial asthma COPD peptic ulcer disease seizure disorders BPH pregnancy
what are some advantages of nonsedating antihistamine?
they do not cross the blood-brain barrier
they have longer durations of action, which allows some of them to be taken only once a day.
Diphenhydramine (Benadryl)
works both peripherally and centrally
potent anticholinergic and sedative effects
use as a hypnotic drug
“hang over” effect = increased potential for falls
most commonly used antihistamines
use for relief or prevention of histamine-mediated allergies
motion sickness
Tx of Parkinson’s disease
promotion of sleep
used in conjunction with epinephrine in the management of anaphylaxis and Tx of acute dystonic reactions
decongestants administered by the oral route
pseudoephedrine
commonly used nasal decongestant spray
phenylephrine
Excessive dosages of decongestants can causes systemic effects elsewhere in the body such as?
hypertension palpitations headache nervousness dizziness
what is the most common adverse effects of intranasal steroids
mucosal irritation and dryness
drug interactions with decongestants
systemic sympathomimetic drugs and sympathomimetic
MAOIs-raising of BP
methyldopa and urinary acidifiers and alkalinizers
what are the advantages of using oral decongestants
the oral route produce prolonged decongestant effects.
the effect is less potent.
no rebound congestion
what is the disadvantages of using topical decongestants
rebound congestion because of the very rapid absorption of drug through mucous membranes.
what are some advantages in using inhaled decongestants
not associated with rebound congestion.
used prophylactically to prevent nasal congestion in patients with chronic upper respiratory tract symptoms.
what are the indications or antitussives
to stop the cough reflex when the cough is nonproductive and or harmful.
what are some contraindications for the use of antitussives
drug allergy.
opioid dependency
high risk for respiratory depression.
what are adverse effects for antitussives
dizziness, headache, pruritus and nasal congestion
dry mouth
sedation, constipation
what are expectorants used for?
The relief of productive cough commonly associated with common cold. bronchitis laryngitis pharyngitis pertussia influenza measles loosening and thinning sputum and bronchial secretions
how long should patients taking chewable tablets of antitussive or lozenges wait before drinking liquids
30 to 35 minutes afterward
Antitussive are for nonproductive coughs True or False
True
a patient with a history of asthma ask the nurse about taking an antihistamine for a “terrible cold” what should be the nurse’s best answers?
The antihistamine dry up secretions; if the patient cannot expectorate the secretion it may become viscous, occlude airways and lead to atelectasis or occlusion of the bronchioles.
