NURS 233 Exam 5 Questions And Correct Answers
What is histamine involved with?
-nerve transmission in CNS
-capillary dilation
-smooth muscle contraction
-gastric acid stimulation
-increase HR
-mild allergic rxns
What are the 2 types of histamine receptors
H1 and H2
Which histamine receptor is involved with capillary dilation and smooth muscle
contraction
H1
Which histamine receptor is involved with gastric acid stimulation and increased HR
H2
Antihistamines _______ with histamine for _________ receptor sites
compete, specific
What do H2 blockers help decrease
gastric acid secretion
What are H1 blockers help with?
,-allergic rhinitis
-anaphylaxis
-angioedema
-drug fevers
-insect bites
-pruritus
what are the drugs to know with antihistamines
-diphenhydramine
-chlorpheniramine
-fexofenadine
-loratadine
-cetirizine
To get the best result when should you start taking antihistamines
as soon as symptoms start
What is the MOA of antihistamines?
Compete with histamines for binding to H1 receptors to prevent a histamine mediated
response (prevent mild allergic rxns)
Does antihistamine knock off histamine when its already bound to the receptor?
no
Contraindications for antihistamine
-asthma attack
-narrow angle glaucoma
,-coronary disease
-resp disease (COPD)
-seizure
-HTN
-Enlarged prostate
Precaution for antihistamine
elderly bc it caused paradoxical effect
paradoxical effect
opposite of the intended drug effect (for antihistamines= restlessness/stressed)
Adverse effects of antihistamines
-drowsiness/sedation
-anti cholinergic effects
What would be examples of anticholinergic effects
-dry eyes
-dry mouth
, -constipation
-urinary retention
How are some ways you can help with the drying effects (anticholinergic effect) of
antihistamines
-saline/eyedrops
-hydrate (drink water)
-sugar free hard candies/gum
-lotion/chapstick
How would you know the antihistamine worked?
-everything drys up
-no nasal congestion/runny nose
-sedation/better sleep
What are some drug interactions that you would watch for when administering
antihistamines?
-allergy testing
-ETOH
-MAOI
-other CNS depressants
-other anticholinergic drugs (OTC cold meds)
When would you withhold antihistamines if the pt. is going to receive allergy testing
What is histamine involved with?
-nerve transmission in CNS
-capillary dilation
-smooth muscle contraction
-gastric acid stimulation
-increase HR
-mild allergic rxns
What are the 2 types of histamine receptors
H1 and H2
Which histamine receptor is involved with capillary dilation and smooth muscle
contraction
H1
Which histamine receptor is involved with gastric acid stimulation and increased HR
H2
Antihistamines _______ with histamine for _________ receptor sites
compete, specific
What do H2 blockers help decrease
gastric acid secretion
What are H1 blockers help with?
,-allergic rhinitis
-anaphylaxis
-angioedema
-drug fevers
-insect bites
-pruritus
what are the drugs to know with antihistamines
-diphenhydramine
-chlorpheniramine
-fexofenadine
-loratadine
-cetirizine
To get the best result when should you start taking antihistamines
as soon as symptoms start
What is the MOA of antihistamines?
Compete with histamines for binding to H1 receptors to prevent a histamine mediated
response (prevent mild allergic rxns)
Does antihistamine knock off histamine when its already bound to the receptor?
no
Contraindications for antihistamine
-asthma attack
-narrow angle glaucoma
,-coronary disease
-resp disease (COPD)
-seizure
-HTN
-Enlarged prostate
Precaution for antihistamine
elderly bc it caused paradoxical effect
paradoxical effect
opposite of the intended drug effect (for antihistamines= restlessness/stressed)
Adverse effects of antihistamines
-drowsiness/sedation
-anti cholinergic effects
What would be examples of anticholinergic effects
-dry eyes
-dry mouth
, -constipation
-urinary retention
How are some ways you can help with the drying effects (anticholinergic effect) of
antihistamines
-saline/eyedrops
-hydrate (drink water)
-sugar free hard candies/gum
-lotion/chapstick
How would you know the antihistamine worked?
-everything drys up
-no nasal congestion/runny nose
-sedation/better sleep
What are some drug interactions that you would watch for when administering
antihistamines?
-allergy testing
-ETOH
-MAOI
-other CNS depressants
-other anticholinergic drugs (OTC cold meds)
When would you withhold antihistamines if the pt. is going to receive allergy testing
