Read Mosby's 2014 Nursing Drug Reference Online
Authors: Linda Skidmore-Roth
Mosby's 2014 Nursing Drug Reference (141 page)
(dox-ay′zoe-sin)
Cardura, Cardura XL
Func. class.:
Peripheral α
1
-adrenergic receptor blocker
Chem. class.:
Quinazoline
Do not confuse:
Cardura
/Coumadin/Cardene/Ridaura
Dilates peripheral blood vessels, lowers peripheral resistance; reduction in B/P results from peripheral α
1
-adrenergic receptors being blocked
Hypertension, urinary outflow obstruction, symptoms of benign prostatic hyperplasia
Hypersensitivity to quinazolines
Precautions:
Pregnancy (C), breastfeeding, children, hepatic disease
Calculator
•
Adult: PO
1 mg/day, increase in stepwise manner to 2, 4, 8 mg/day as needed at 1-2 wk intervals, max 8 mg
•
Adult: PO
1 mg/day increasing up to 16 mg/day if required; usual range 4-16 mg/day
• Geriatric: PO
0.5 mg nightly, gradually increase
Available forms:
Tabs 1, 2, 4, 8 mg; ext rel tabs 4, 8 mg
•
Store in tight container at room temperature
•
Tabs
broken, crushed, or chewed; if chewed, will be bitter; do not break, crush, chew XL tabs
•
Immediate release tab:
without regard to meals;
ext rel tabs:
give with breakfast; when switching from immediate release to ext rel, the final evening dose of immediate release should not be taken
CNS:
Dizziness
, headache, drowsiness, anxiety, depression, vertigo, weakness, fatigue, asthenia
CV:
Palpitations,
orthostatic hypotension
, tachycardia, edema,
dysrhythmias,
chest pain
EENT:
Epistaxis, tinnitus, dry mouth, red sclera, pharyngitis, rhinitis
GI:
Nausea, vomiting, diarrhea, constipation, abdominal pain
GU:
Incontinence, polyuria, priapism
PO:
Onset 2 hr, peak 2-6 hr, duration 6-12 hr, half-life 22 hr, metabolized in liver, excreted via bile/feces (<63%) and in urine (9%), extensively protein bound (98%)
Increase:
hypotensive effects—alcohol, other antihypertensives, sildenafil, vardenafil, nitrates
Decrease:
antihypertensive effects of cloNIDine
•
Hypertension:
B/P (lying, standing), pulse 2-6 hr after each dose, with each increase; postural effects may occur, crackles, dyspnea, orthopnea with B/P; pulse; jugular venous distention during beginning treatment
•
BPH:
urinary pattern changes (hesitancy, dribbling, incomplete bladder emptying, dysuria, urgency, nocturia, urgency incontinence, intermittency) before and during treatment
•
I&O, weight daily; edema in feet, legs daily
•
Therapeutic response: decreased B/P; decreased symptoms of BPH
•
That fainting occasionally occurs after 1st dose; not to drive, operate machinery for 4 hr after 1st dose, after dosage increase; to take 1st dose at bedtime; may take 1-2 wk to respond with BPH
Administer volume expanders or vasopressors; discontinue product; place patient in supine position
Canada only Side effects:
italics
= common;
bold
= life-threatening 
Nurse Alert
(dox′e-pin)
Prudoxin Cream, Silenor, Zonalon Topical Cream
Func. class.:
Antidepressant, tricyclic, antihistamine (topical)
Chem. class.:
Dibenzoxepin, tertiary amine
Blocks reuptake of norepinephrine, serotonin into nerve endings, increasing action of norepinephrine, serotonin in nerve cells
Major depression, anxiety;
topical:
lichen simplex, atopic dermatitis, eczema
Unlabeled uses:
Topical pruritus, insomnia, migraine prophylaxis
Hypersensitivity to tricyclics, urinary retention, closed-angle glaucoma, prostatic hypertrophy, acute recovery from MI
Precautions:
Pregnancy (C) (PO) (B) (topical), breastfeeding, geriatric patients, seizures
Black Box Warning:
Children, suicidal patients
Calculator
•
Adult: PO
50-75 mg/day, may increase to 300 mg/day for severely ill; give in divided doses if >150 mg/day
• Geriatric: PO
25-50 mg at bedtime, increase weekly by 25-50 mg to desired dose, max 150 mg/day
•
Adult: PO
10 mg at bedtime, may increase to 25 mg at bedtime;
TOP
apply thin film qid at least 3 hr apart
•
Adult: PO
6 mg 30 min before bedtime, 3 mg may be sufficient, max 6 mg/night
Available forms:
Caps 10, 25, 50, 75, 100, 150 mg; oral conc 10 mg/ml; cream 5%; tabs (Silenor) 3, 6 mg
•
Oral conc:
should be diluted with 120 ml water, milk or orange, grapefruit, tomato, prune, or pineapple juice; do not mix with grape juice
•
Increased fluids, bulk in diet for constipation
•
With food, milk for GI symptoms; do not give with carbonated beverages
•
Dosage at bedtime to avoid oversedation during day; may take entire dose at bedtime; geriatric patients may not tolerate daily dosing
•
Gum, hard candy, or frequent sips of water for dry mouth
•
Topical:
by applying to affected area, rub slightly; do not use occlusive dressings
CNS:
Dizziness, drowsiness
, confusion, headache, anxiety, tremors, stimulation, weakness, insomnia, nightmares, EPS (geriatric patients), increased psychiatric symptoms, paresthesia,
suicidal ideation
CV:
Orthostatic hypotension, ECG changes, tachycardia
,
hypertension,
palpitations,
dysrhythmias
EENT:
Blurred vision
, tinnitus, mydriasis, ophthalmoplegia, glossitis
GI:
Diarrhea, dry mouth
, nausea, vomiting,
paralytic ileus,
increased appetite, cramps, epigastric distress, jaundice,
hepatitis,
stomatitis, constipation
GU:
Urinary retention
,
acute renal failure
HEMA:
Agranulocytosis, thrombocytopenia, eosinophilia, leukopenia,
pancytopenia, purpuric disorder
INTEG:
Rash, urticaria, sweating, pruritus, photosensitivity
PO:
Steady state 2-8 days, metabolized by liver, excreted by kidneys, crosses placenta, excreted in breast milk, half-life 8-24 hr
Increase:
hyperpyretic crisis, seizures, hypertensive episode—MAOIs
Increase:
hypertensive action—EPINEPHrine, norepinephrine
Increase:
hypertensive crisis—cloNIDine; do not use together
Increase:
doxepin effect—cimetidine, FLUoxetine, fluvoxaMINE, PARoxetine, sertraline
Increase:
CNS depression—barbiturates, benzodiazepines, sedative/hypnotics, alcohol, other CNS depressants
Increase:
QT interval: class IC/III antiarrhythmics (propafenone, flecainide), quinolones
Increase:
toxicity—SSRIs, SNRIs, serotonin-receptor agonists
Increase:
anticholinergic effects—anticholinergics
•
Serotonin syndrome: St. John’s wort
Increase:
serum bilirubin, blood glucose, alk phos, LFTs
•
B/P (lying, standing), pulse q4hr; if systolic B/P drops 20 mm Hg, hold product, notify prescriber; VS q4hr in patients with CV disease
•
Blood studies: CBC, leukocytes, differential, cardiac enzymes if patient is receiving long-term therapy
•
Hepatic studies: AST, ALT, bilirubin
•
Weight weekly; appetite may increase with product
•
ECG
for flattening of
T
wave, bundle branch block, AV block, dysrhythmias in cardiac patients; product should be discontinued gradually several days before surgery
•
EPS
primarily in geriatric patients: rigidity, dystonia, akathisia
•
Depression:
mood, sensorium, affect, suicidal tendencies, increase in psychiatric symptoms
•
Chronic pain:
location, severity, type before and during treatment, alleviating/aggravating factors
•
Urinary retention, constipation; constipation most likely in children, geriatric patients
•
Withdrawal symptoms:
headache, nausea, vomiting, muscle pain, weakness; not usual unless product is discontinued abruptly
•
Alcohol consumption; if alcohol is consumed, hold dose until morning
•
Storage in tight container protected from direct sunlight
•
Assistance with ambulation during beginning therapy because drowsiness/dizziness occurs; safety measures primarily for geriatric patients
•
Check to confirm that PO medication is swallowed
•
Therapeutic response: decreased anxiety, depression
•
That therapeutic effect (depression) may take 2-3 wk, antianxiety effects sooner
•
To use caution when driving, during other activities requiring alertness because of drowsiness, dizziness, blurred vision
•
To avoid alcohol, other CNS depressants; may potentiate effects
•
Not to discontinue medication abruptly after long-term use; may cause nausea, headache, malaise
•
To wear sunscreen or large hat; photosensitivity occurs
•
That clinical worsening and suicide may occur
•
To immediately report urinary retention
ECG monitoring; lavage, activated charcoal; administer anticonvulsant, sodium bicarbonate