asthma meds Flashcards
1
Q
what is the step up therapy approach?
A
- start tx at step appropriate to asthma severity at time of eval: if not achieved gradually step up therapy until successful
- gradually increase and add options
- consider alt. explanations for poor asthma control
- consider asthma specialist consult
2
Q
What is the step down therapy approach?
A
- tx exacerbation sxs aggressively
- gradual reduction of long term control meds to lowest level possible to achieve max control
- continue to attempt reduction of daily oral steroid use
3
Q
What do quick relief meds do?
A
- inhibit smooth muscle contraction
- these are Short acting b2 agonists
4
Q
What do the long term control meds do? examples?
A
- prevent and/or reverse inflammation (Most effective approach):
anticholinergics, corticosteroids, mast cell stabilizing agents, leukotriene modifiers, methylanxthines - inhibit smooth muscle contraction: LABA
5
Q
What are the different admin. techniques?
A
- MDI: metered dose inhaler, releases specific amt of aerosolized particles, use a spacer
- nebulizer: liquid medicine used in a machine, provides nebulized particles with moist continuous airflow. Ideal for peds or those unable to use MDI
- inhaled powder: rotacaps, disc-haler, mechanical crushing of tablet or capsule releases powder for inhalation
- systemic admin: oral or parenteral routes (SQ, IM, IV), generally assoc with more side effects
6
Q
What are the sympathomimetics bronchodilators or B2 agonists?
A
- produce airway dilation
- stimulation of Beta-adrenergic receptors
- activation of G proteins with resultant formation of cyclic AMP
- decrease release of mediators
- improve mucociliary transport
- short acting: effective for acute attack (rescue) and prevention of exercise induced bronchospasm
- long acting: effective for prevention and maintenance therapy
7
Q
What is the most widely used B agonist?
A
- albuterol (proventil, ventolin)
- beta-2 selective
- rescue med
- active by all routes: inhalation increases bronchial selectivity, more rapid onset, oral and IV admin (offers no advantages over inhaled)
- quick onset, lasts 4-6 hrs
8
Q
What are the other short acting B 2 agonists?
A
- Terbutaline (Brethine): also used to prevent uterine contractions
- Bitolterol (Tornalate)
- Pirbuterol (Maxair)
- these are all similar to albuterol
9
Q
What is usualy dosing for B2 agonists?
A
- MDI: 2-4 puffs q 4-6 h and prn
- increasing use more than 1 canister (200 puffs) per month signals lack of adequate asthma control
- more frequent use associated with more adverse effects
10
Q
What are the adverse effects of B-2 agonists?
A
- tachycardia
- tremor
- hypokalemia
- HA
- hyperglycemia
- increased lactic acid
11
Q
What are the LABAs?
A
- salmeterol (Serevent) inhaled
- Formoterol (Foradil) inhaled: oral - sustained release albuterol, not rescue drugs for breakthrough sxs, admin of extra doses can cause cumulative SEs
- these have slower onset, long lasting (9-12 hours), widely used for maintenance, not recommended for tx of acute episodes: slow onset of action (approx 30 min)
- Newer LABAs:
Levalbuterol (Xopenex): long acting, may have more beta-2 selectivity than albuterol
Fenoterol (Berotec): available in Canada, soon in US, similar to albuterol or terbutaline
12
Q
What are the anticholinergics used? what effects do they have?
A
- ipratropium bromide (Atrovent): may enhance bronchodilation achieved by beta agonists, main use is in combo with Beta agonist
- slow to act: 60-90 minutes, minimal side effects: beneficial with pts with heart disease
- modest potency, doesn’t block Exercise induced, and doesnt modify rxn to antigen
- Tiotropium (Spiriva): same profile as ipratropium, but longer acting (24 hours)
13
Q
What is the methylxanthine bronchodilator? Use?
A
- theophylline
- medium potency bronchodilator
- undefined MOA
- therapeutic plasma concentrations 10-15 mcg/mL (narrow window, hard to achieve and maintain)
- some recommend even 8-12 mcg/ml
- dose required to achieve desired plasma level varies widely from pt to pt
14
Q
What factors decrease theophylline clearance? increase clearance?
A
- neonates
- elderly
- acute and chronic hepatic dysfxn
- cardiac decompensation, cor pulmonale
- febrile illnesses
- concurrent use of macrolide abx, quinolone, allopurinol, propranolol
- Clearance is increased in children and concurrent use of cigarettes, marijuana, phenobarbital, and phenytoin
15
Q
Maintenance therapy of theophylline?
A
- long acting theophylline compounds (Slo-bid) - usually give 1 or 2 a day or once daily
16
Q
Most common SEs of Theophylline?
A
- insomnia, nervousness, N/V, anorexia, HA, and tachycardia
- plasma levels greater than 30 g/mL - risk of seizures and cardiac arrhythmias
17
Q
Theophylline dosing?
A
- start with 16 mg/kg/day or 400 mg/day in divided doses
- adjust dose based on clinical response, SEs and serum levels
- single dose admin in evening reduces nocturnal sxs
- if serum level is more than 30 mcg/ml than skip 2 doses and reduce dose by 50%
18
Q
How should you monitor theophylline?
A
- if pt is stable: measure serum levels q 6-12 months
- if pt is showing toxicity or breakthrough sxs adjust dose and recheck serum levels in 3 days
19
Q
What is the IV methylxanthine called? -
A
- aminophylline (IV theophylline)
20
Q
How do corticosteroids work?
A
- not bronchodilators
- reduce inflammation
- use with acute illness: severe airway obstruction is not resolving or is worsening
- use with chronic disease: failure of a previously optimal regimen with frequent recurrences of sxs of increasing severity
- inhaled steroids: reduce airway reactivity, start aerosolized steroids in any pt who isn’t controlled by bronchodilators, if sxs aren’t eliminated by std dose, than increase 2 fold or more
- alternative to oral glucocorticoids
- greatly facilitate withdrawal of oral steroids
21
Q
What are the SEs of corticosteroids?
A
- Thrush
- dysphonia
- larger doses: adrenal suppression, cataract formation, decreased growth in children, interference with bone metabolism, and purpura
- it takes 2-4 weeks to produce a beneficial effect (may need to start short course of oral glucocorticoids simultaneously with inhaled drug
22
Q
Corticosteroid class: in order from highest potency to lowest?
A
- fluticasone (flovent)
- Budesonide (Pulmicort)
- beclomethasone (Vanceril, Beclvent, QVAR)
- Triamcinolone (Azmacort)
- Flunisolide (aerobid, Aerobid-M)
23
Q
What are the pros about Budesonide (Pulmicort respules) which is a newer agent?
A
- administered by turbuhaler, DPI, or nebulizer
- first nebulized corticosteroid
- studied in children aged 6 mo to 8 yrs
- greater number of sx free days
- decreased need for B agonists
- reduced hospitalization rates
24
Q
What PO steroids are used in acute settings?
A
- methylprednisolone - IV (attack)
- Prednisone 60 mh po can be subsituted
- rapid tapering of glucocorticoids frequently results in recurrent obstruction
- reducing dose by 1/2 every 3-5 days following an acute episode
25
Q
Use of PO steroids for chronic tx?
A
- alt. day schedule
to minimize side effects - continuous corticosteroid admin. interrupts growth
- long acting preps (dexamethasone) shouldnt be used: prolonged suppression of pituitary adrenal axis
26
Q
What are the newer combo agents?
A
- advair diskus: fluticasone+salmeterol
dry powder for inhalation - combivent MDI: ipratropium + albuterol, Duoneb for neb
27
Q
What are the mast cell stabilizers? What do they do?When are they the most effective?
A
- antiinflammatory
- cromolyn (Intal), Nedocromil (Tilade)
- don’t influence airway tone
- inhibit degranulation of mast cells
- Prevent release of chemical mediators of anaphylaxis
- most effective for seasonal disease: 4-6 weeks before beneficial effects
- dose: 2 puffs qid
- prophylactically 15-20 min pre contact with precipitant
28
Q
leukotriene inhibitors function and examples?
A
- anti-inflammatory
- montelukast (singulair): 5 mg qd (chewable tablet)
- zafirlukast (accolate)
- zileuton (leutrol, zyflo)
- MOA: suppress action of cysteinyl leukotriene (proinflammatory mediators involved in asthma pathogenesis)
29
Q
Use of leukotriene inhibitors?
SEs?
A
- improvement in FEV1, asthma exacerbations
- improvement in frequency of prn b-agonist use
- safe in children ages 6-14
- adverse SEs minimal
- effective in combo with corticosteroid or B-agonist
- alt to inhaled corticosteroid
- add on therapy when response to inhaled corticosteroids is suboptimal
- help reduce higher doses of inhaled corticosteroids
- not for reversal of acute attack (onset 1 hr)
- SEs:
LFT abnormalities, HA
30
Q
What is omalizumab used for?
A
- newer approach to tx of asthma
- inhibits the binding of IgE to mast cells
- Doesn’t promote mast cell degranulation to already bound IgE
- lowers plasma IgE to undetectable levels
- clinical trials have shown repeated IV or SQ injection to lessen asthma severity and reduce the corticosteroid requirement in pts with moderate to sever asthma
31
Q
Tx for step 1 intermittent?
A
- tx: quick relief: prn SABA if you use more than 2x a week might need to start long term control therapy
32
Q
Tx for step 2 mild persistent?
A
- quick relief: prn SABA
- 1 daily long term control med:
inhaled cortico (low) or -cromolyn or nedrocromil - 2nd line choices: leukotriene modifier or theophylline
33
Q
Step 3: moderate persistent tx?
A
- tx: quick relief - SABA
- long term control:
inhaled corticosteroid (Medium) or low dose + LABA (salmeterol) or sustained release Theophylline - if needed (medium- high dose) inhaled corticosteroid + LABA or sustained release theophylline
34
Q
Step 4: severe persistent tx?
A
Tx: quick relief - prn SABA
- long term control: high dose inhaled cortico + LABA or sustained theophylline or LABA + oral corticosteroids
35
Q
Tx for allergic asthmatic?
A
- elimination of causative agent:
ASA even in small quantities - other NSAIDs: ibuprofen, naproxen
- Tartraxine (coloring agent)
- sulfiting agets (preservatives)
- desensitization or immunotherapy not proven highly effective
- change of occupation or relocation of dwelling: significant role
- eliminating aerosol sprays such as deodorants, hair sprays, and insecticides from the household
36
Q
Since asthmatics are at High risk for other diseases what is impt for them to have?
A
- immunizations:
yearly influenza vaccination and pneumococcal vaccine
