Exam 2 - URI Pharmacology Flashcards
what is histamine
substance involved in nerve transmission, capillary dilation, smooth muscle contraction, gastric acid secretion and HR control
what is H1 histamine
- receptors which mediate smooth muscle contraction and capillary dilation which is the target for traditional ‘allergy’ medications
what is H2 histamine
- mediation heart rate and gastric acid secretion
what happens in excessive amounts of histamine are released
- can lead to anaphylactic and severe allergic symptoms
H2 blockers
- cimetidine, ranitidine, famotidine, nizatidine
- act on the GI system
- GERD treatment most common
H1 blockers - antihistamines
- can be sedating and non-sedating
- usually used to treat nasal allergies, seasonal allergies, sneezing, runny nose
- palliative not curative
MOA: H1 blockers - antihistamines
- bind to H1 receptors and block histamine release
- have a mild anticholinergic effect
contraindications for all H1 blockers
- closed angle glaucoma
- cardiac disease
- kidney disease
- hypertension
- bronchial asthma
- COPD
- PUD
- seizures
- BPH
- pregnancy
sedating antihistamine drug
diphenhydramine
indications for sedating antihistamines
- mild allergic reactions, motion sickness, insomnia
- can be given with severe anaphylactic reactions
side effects of sedating antihistamines
- drowsiness
- dry mouth
- urinary retention
- constipation = DRY
nursing implication for sedating antihistamines
- monitor closely for dizziness when ambulating
- monitor for urinary retention
- monitor for constipation
what should you avoid if you are taking a sedating antihistamine
- driving and activities requiring mental alertness
non-sedating antihistamine drugs
- loratadine
- fexofenadine
- cetirizine
indications for non-sedating antihistamines
- allergic rhinitis
- chronic idiopathic urticaria
side effects of non-sedating antihistamines
- fewer side effects
- less drowsiness and fatigue
sympathomimetics (decongestant) drugs
- phenylephrine
- pseudoephedrine
indications for sympathomimetics
- reduce nasal congestion
- allergic rhinitis
- sinusitis
- common cold
MOA: sympathomimetics
- mimics the action of SNS, activates alpha1-adrenergic receptors which causes vasoconstriction of blood vessels, causing nasal turbinates to shrink and opens nasal passages
side effects for sympathomimetics
- all related to CNS stimulation
- agitation
- insomnia
- anxiety
- tachycardia
- heart palpitations
patient education for sympathomimetics
- do not use for more than 4 days
- rebound nasal congestion occurs if drug is abruptly stopped after prolonged use
- tapering off is recommended
pseudoephedrine considerations
- potential for abuse
- one of the active ingredients is methamphetamine
- OTC, but must get at pharmaceutical counter
- limit on how much people can get
antitussive drugs
- dextromethorphan
- codeine
- benzonatate
indications for antitussives
- cough suppressant
- acute or chronic coughs
MOA: antitussive
- directly suppresses the cough reflex in the brain
side effects of antitussives
- CNS depressant
- do NOT take with other CNS depressants
- potential for abuse
expectorant drug
- guaifenesin
indication for expectorant
- decrease mucus in colds
- bronchitis
MOA: expectorant
- reduction in surface tension of secretion helping thin the mucus making it easier to expectorate
nursing indications for expectorants
- encourage fluid to help thin secretions
- be careful in patients with chronic cough or asthma
mucolytics drug
- acetylcysteine
indication for mucolytics
- bronchopulmonary disease
- cystic fibrosis
MOA: mucolytics
- decreases viscosity of mucus making it easier to cough
side effects of mucolytics
- bronchospasm may occur
- smells terrible
