Test 2 Pharmacology Part 2 Flashcards
1
Q
Antihistamines
A
Drugs that directly compete with histamine for specific receptor sites
Two histamine receptors
- H1 histamine - 1
- H2 histamine - 2
2
Q
H1 receptor antagonists
A
- ex: benadryl
- inhibit smooth muscle constriction in blood vessels and respiratory and GI tracts
- decrease capillary permeability
- decrease salivation and tear formation
- used for a variety of allergic disorders to prevent or reverse target organ inflammation
3
Q
First-generation H1 Receptor Antagonists
A
- non-selective/sedating
- bind to both central and peripheral H1 receptors
- usually cause CNS depression (drowsiness, sedation) but may cause CNS stimulation (anxiety, agitiation), especially in children and elderly
- also have substantial anticholinergic effects
4
Q
Examples of 1st generation H1 receptor antagonists
A
- chorpheniramine: elixir and expectorant
- hydroxyzine (Visterel)
- diphenhydramine (Benadryl)
- promethazine
5
Q
First-Generation Side Effects
A
- sedation
- dry mouth
- blurred vision
- GI disturbances
- headache
- urinary retention
- hydroxyzine is not recommended for pregnancy and breast feeding
6
Q
Second-Generation H1 receptor antagonists
A
- selective/non-sedating
- cause less CNS depression b/c they are selective for peripheral H1 receptors and do not cross BBB
- longer-acting compared to 1st generation
7
Q
Examples of Second-generation H1 receptor antagonists
A
- cetirizine (Zyrtec)
- loratadine (Claritin)
8
Q
Second-generation side effects
A
- may cause slight sedation
- some antihistamines may interact with antifungal, e.g. ketoconazole; antibiotics, e.g. erythromycin; prokinetic drug–cisapride or grapefruit juice, leading to potentially serious ECG changes e.g. Terfenadine
9
Q
Nursing Implication: Antihistamines
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 disease
- use w/ caution in increase intraocular pressure, cardiac or renal disease, hypertension, asthma, COPD, peptic ulcer disease, BPH, or pregnancy
- instruct patients to report excessive sedation, confusion, or HTN
- avoid driving/operating heavy machinery and do no consume alcohol or other CNS depressants
- don’t take with other prescribed or OTC meds w/o checking w/ prescriber
- best tolerated when taken w/ meals, less GI upset
- if drymouth occurs, teach patient to perform frequent mouth care, chew gum, or suck on hard candy
- monitor intended therapeutic effects
10
Q
Decongestans: 2 main types
A
- adrenergics (largest group)
- corticosteroids
11
Q
Oral decongestants
A
- prolonged decongestant effects, but delayed onset
- effect less potent that topical
- no rebound congestion
- exclusively adrenergics
- examples: phenylephrine and pseudoephedrine (Sudafed)
12
Q
Topical Nasal Decongestants
A
- both adrenergics and steroids
- prompt onset
- potent
- sustained use over several days cuases rebound congestion, making the condition worse
13
Q
2 categories of Topical Nasal Decongestants
A
- adrenergics
- ephedrine (Vicks)
- oxymetazoline (Afrin)
- naphazoline (Privine)
- phenylephrine (Neo Synephrine)
- Intranasal Steroids
- beclomethasone dipropionate (Beconase, Vancenase)
- flunisolide (Nasalide)
14
Q
Nasal Decongestants: Side Effects
A
- adrenergics
- nervousness, insomnia, palpitations, tremors, (systemic effects due to adrenergic stimulation of the heart, blood vessels, and CNS)
- steroids
- local mucosal dryness and irritation
- rebound congestions develops with topical agents when used more than a few days
- CNS stimulation occurs with oral sympathomimetics
15
Q
Decongestants: Nursing Implications
A
- pts should avoid caffeine
- report a fever, cough, or other symptoms lasting longer than a week
- monitor for intended therapeutic effects
16
Q
3 classes of cough preparations
A
- antitussives
- expectorants
- mucolytics
17
Q
Antitussives
A
- drugs used to stop or reduce coughing
- opiod and nonopioid (narcotic and non-narcotic)
- Use only for nonproductive coughs!
- some act w/in the CNS, some act peripherally
- indicated in dry, hacking, nonproductive cough that interfere with rest and sleep
18
Q
Antitussives: Examples
A
- codeine phosphate
- pholcodine
- dextromethorphan
- diphenhydramine
19
Q
Antitussives: side effects
A
- Benzonatate
- dizziness, headache, sedation
- Dextromethorphan
- dizziness, drowsiness, nausea
- Opioids
- sedation, nausea, vomiting, lightheadedness, constiptation
20
Q
Antitussives: Nursing Implications
A
- perform respiratory and cough assessment, and assess for allergies
- instruct patients to avoid driving or operating heavy equipment due to possible sedation, drowsiness, or dizziness
- if takin chewable tables or lozenges, don’t drink for 30 to 35 minues afterward
- report any of the following to caregiver
- cough lasting more than a week, persistant headache, fever, rash
- antitussives are for NONPRODUCTIVE coughs
- monitor for intended therapeutic effects
21
Q
Expectorants
A
- aid in the removal of mucus
- reduce viscosity of secretions
- disintegrate and thin secretions
- Guafenesin is most commonly used
- Ammonia & Ipecacuaha Mixture is another one
- stimulate flow of respiratory tract secretions
22
Q
Expectorants: Side effects
A
- guafenesin
- nausea, vomiting, gastric irritation
- terpin hydrate
- gastric upset
- elixir has high alcohol content
23
Q
Expectorants: Nursing Implications
A
- should be used w/ caution in the elderly or those with asthma or respiratory insufficiency
- should receive more fluids, if permitted, to help loosen and liquefy secretions
- report a fever, cough, or other symptoms lasting longer than a week
- monitor for intended therapeutic effects
24
Q
Mucolytics
A
- reacts directly with mucus to make it more watery. This should help make the cough more productive
- acetylcysteine
- bromhexine
- carbocisteine
25
TB: 1st line drugs
* high efficacy, low toxicity
* Isoniazid (INH)
* Pyrazinamide
* Ethambutol
* Streptomycin
26
TB: 2nd line drugs
* low efficacy, high toxicity, or both
* ethionamide
* para aminosalicylic acid
* cycloserine
* amikacin/capreomycin
* fluoroquinolones
* rifabutin
27
Isoniazid (isonicotinic acid hydrazide, H)
Antitubercular Agent
* essential component of all anti TB regiemn (except intolerance to H or resistance)
* is is tuberculocidal: kills fast multiplying organism and inhibit slow acting organism
* acts on both intracellular (present in macrophages) and extracellular bacilli
* is the cheapes AT agent
28
Rifampin (Rifampicin, R)
* semisythetic derivative of Rifamycin B from Steptomyces mediterranei
* bactericidal to M. Tuberculosis and others
* S. aureus
* N. Meniingitidis
* H. influenzae
* E. coli
* Klebsiella
* Proteus
* Legionella
29
Pyrazinamide (Z)
* Chemically similar to INH
* weak tuberculocidal, more active in acidic medium
* more lethal to intracellular bacilli and to those at sites showing inflammatory response (Therefore effective in first 2 months of therapy where inflammatory changes are present)
30
Ethambutaol (E)
* tuberculostatic, clinically active as Streptomycin
* fast multiplying bacteria are more sensititve
* also acts against atypical mycobacteria
* if added in triple regimen (RZH) it is found to hasten the rate of sputum conversion and to prevent development of resistance
31
Streptomycin (S)
* it was 1st clinically usefull antibiotic drug
* it is protein synthesis inhibitor by combining with 30S ribosome
* it is tuberculocidal, but less effective than INH/Rifampicin
* acts on extracellular bacilli only (poor penetration in the cells)
32
Antivirals
* key characteristics
* able to enter the cells infected with virus
* interfere with viral nucleic acid synthesis and/or regulation
* some drugs interfere with ability of virus to bind to cells
* some drugs stimulate the body's immune system
* best responsed to antiviral drugs are in patients with competent immune systems
* a healthy immune system works synergistically with the drug to eliminate or suprress viral activity
33
Amantadine (Symmetrel)
* Antiviral - nonretroviral
* narrow antiviral spectrum-active only against influenza A
* used prophylactically when vaccine is not available or cannot be given
* therapeutic use can reduce recovery time
* CNS effects: insomnia, nervousness, lightheadedness
* GI effects: anorexia, nausea, others
34
Remantadine (Flumadine)
* same spectrum of activity, mechanism of action and indications as amantadine
* fewer CNS effects
* causes less GI upset
35
Ribaviring
* Antiviral - nonretroviral
* synthetic nucleoside analog
* given orally, or oral or nasal inhalation
* inhalation form (Virazole) used for hospitalzied infants with RSV (respiratory syncytialvirus) infections
36
Amphotericin B and Nystatin
* fungal meningitis
* bind to the funcal cell membrante component ergosterol, leading to increased fungal cell membrane permeability and the loss of intracellular constitutents
* Amphotericin B has activity agains Candida spp., Cryptococcus neoformans, Blastomyces dermatitidis, histoplasma capsulatum, sporothrix schenckii, coccidioides immitis, peracoccidioides braziliensis, aspergillus spp., Penicillium marneffei, etc.
37
Major acute reaction to IV Amphotericin B
* fever and chills
* tachypnea and respiratory stirdor
* modest hypotension
* patients with preexisting cardiac or pulmonary disease may develop hypoxia or hypotension
* although the reaction ends spontaneously in 30 to 45 minutes
38
Nystatin
* a polyene antifungal drug with a ring structure and a mechanism of action similar to that of amphotericin B
* too toxic for systemic use, nystatin is limited to the topical treatment of superficial infections caused by C. albicans
* infections commonly treated by this drug include oral candidiasis (thrush), mild esophageal candidiasis, and vaginitis
39
Fluconazole
* anti-fungal
* doesn't require an acidic environment, as does ketoconazole, for GI absorption
* about 80 to 90% of an orally administered dose is absorbed, yielding high serum drug levels
* penetrates widely into most body tissues
* cerebrospinal fluid levels are 60 to 80% of serum levels permitting effective treatment for fungal meningitis
* about 80% of the drug is excreted unchanged in the urine
* dosage reducetions are required in the presence of renal insufficiencty
* well tolerated
40
Fluconazole side effects
* asymptomatic liver inzyme elevation
* drug associated hepatic necrosis has been reported
* alopeica has been reported as a commong adverse event
* coadministration of enzyme inhibitor fluconazole with phenytoin results in increased serum phenytoin levels
41
dornase alfa (Pulmozyme)
* CF drug
* hydrolyzes the DNA in sputum of CF patients and reduces sputum viscosity and viscoelasticity
* contraindications: allergic
* side effects:
* serious side effects are: an allergic reaction (difficulty breathing, closing of the throat, swellin of the lips, tongue, or face, or hives), increased difficulty breathing, chest pain, fever
* less serious side effects: voice alteration, sore throat, rash, laryngitis, eye redness, irritation, inflammation, nasal stuffiness or discharge
* Drug interraction
* Afrezza (insulin inhalation, rapid acting)
* insulin inhalation, rapid acting
* Exubera (insulin inhalation, rapid acting)
42
Nicotine Replacment Oral Agents
* nicotine gum
* nicotine inhaler
* nicotine lozenge
* nicotine nasal spray
* nicotine patch
* buppropion SR
* Varenicline
43
Buproprion SR (Wellbutrin)
* Advantages
* oral formulation given BID that is easy to use
* may be beneficial for patients with coexisting depression
* initiated before quit date
* no risk of nicotine toxicity if patient continues to smoke
* Disadvantages
* increased seizure risk
* several contraindications and precautions that may preclude use
* side effects of insomnia and dry mouth
44
varenicline (Chantix)
* advantages
* oral formulatin given BID that is easy to use
* intiate before quit date
* new mechanism of action for persons who previously failed using other medications
* disadvantages
* may induce nausea in up to 1/3 of patients (need to titrate)
* post-marketing surveillance data stimulated FDA warning
