Read Mosby's 2014 Nursing Drug Reference Online
Authors: Linda Skidmore-Roth
Mosby's 2014 Nursing Drug Reference (390 page)
(thee-off′i-lin)
Phyllocontin
, Theochron, Theo-24, Uniphyl
Func. class.:
Bronchodilator, spasmolytic
Chem. class.:
Methylxanthine
Exact mechanism unknown, relaxes smooth muscle of respiratory system by blocking phosphodiesterase, which increases cAMP; increased cAMP alters intracellular calcium ion movements; produces bronchodilation, increased pulmonary blood flow, relaxation of respiratory tract
Bronchial asthma, bronchospasm associated with chronic bronchitis, emphysema, apnea during infancy for respiratory/myocardial stimulation
Unlabeled uses:
Methotrexate toxicity, sleep apnea, status asthmaticus
Hypersensitivity to xanthines, tachydysrhythmias
Precautions:
Pregnancy (C), breastfeeding, children, geriatric patients, CHF, cor pulmonale, hepatic disease, diabetes mellitus, hyperthyroidism, hypertension, seizure disorder, irritation of the rectum/lower colon, alcoholism, active peptic ulcer disease
Calculator
Calculate initial mg/kg dose based on ideal body weight as theophylline distributes poorly into body fat
• Adult <60 yr/adolescent ≥16 yr:
IV CONT INF
expressed in theophylline; initially, 0.4 mg/kg/hr; max 900 mg/day (otherwise healthy nonsmokers); patients who smoke may require an increased dose; give 0.2 mg/kg/hr (≥400 mg/day) in CHF, cor pulmonale, liver dysfunction, sepsis with multiorgan failure, shock; reduced doses may be needed in patients receiving other drugs that decrease theophylline clearance; adjust dosage based on serum concentrations
• Adult ≥60 yr:
IV CONT INF
initially, 0.3 mg/kg/hour; give 0.2 mg/kg/hr in CHF, cor pulmonale, liver dysfunction, sepsis with multiorgan failure, shock; reduced doses may be needed in patients receiving other drugs that decrease theophylline clearance; adjust dosage based serum concentrations; max 400 mg/day unless serum concentration and patient condition require a higher dose
• Child ≥12 yr/adolescent ≥15 yr:
IV CONT INF
Initially, 0.5 mg/kg/hr (healthy nonsmokers (up to 900 mg/day); 0.7 mg/kg/hr in smokers; 0.2 mg/kg/hr (up to 400 mg/day) in cardiac decompensation, cor pulmonale, liver dysfunction, sepsis with multiorgan failure, or shock); adjust dosage based on serum concentrations
• Child 9-11 yr:
IV CONT INF
Initially, 0.7 mg/kg/hr; reduced doses may be needed in patients receiving other drugs that decrease theophylline clearance; give 0.2 mg/kg/hr (up to 400 mg/day) in cardiac decompensation, cor pulmonale, liver dysfunction, sepsis with multiorgan failure, or shock; adjust dosage based on serum concentrations
• Child 1-8 yr:
IV CONT INF
Initially, 0.8 mg/kg/hr; reduced doses may be needed in patients receiving other drugs that decrease theophylline clearance; 0.2 mg/kg/hr (up to 400 mg/day) in cardiac decompensation, cor pulmonale, liver dysfunction, sepsis with multiorgan failure, or shock; adjust dosage based on serum concentrations
• Infant 6-52 wk:
IV CONT INF
Calculate initial dosage using the following equation: (0.008 × age in wk) + 0.21 = theophylline dosage in mg/kg/hr IV; reduced doses may be needed in patients with risk factors for reduced theophylline clearance (cimetidine therapy, cardiac or liver dysfunction, renal impairment in infant <3 mo); adjust dosage based on serum concentrations
• Adult/adolescent/child >45 kg:
PO
(expressed in theophylline and reg r
elease products) PO Initially, 300 mg/day in divided doses q6-8hr; after 3 days, if tolerated, increase dose to 400 mg/day in divided doses q6-8hr; after 3 more days, if tolerated, increase dose to 600 mg/day PO in divided doses q6-8hr; adjust dose to maintain therapeutic range; doses of 400-1600 mg/day may be needed, max 400 mg/day in patients with risk factors for decreased theophylline clearance (elderly patients >60 yr); NIH recommends initial dose for asthma of 10 mg/kg/day (max: 300 mg/day) titrated to serum concentration of 5-15 mcg/ml (usual max: 800 mg/day in ≥12 yr and 16 mg/kg/day in children 1-11 yr)
• Child/adolescent ≤15 yr old and ≤45 kg:
PO
Initially, 12-14 mg/kg (max 300 mg) per day in divided doses q4-6hr; after 3 days, if tolerated, may increase to 16 mg/kg (max 400 mg) per day in divided doses q4-6hr; after 3 more days, if tolerated and if needed, increase dose to 20 mg/kg (max 600 mg) per day in divided doses q4-6hr; adjust dose to maintain therapeutic range (doses of 10-36 mg/kg/day in child 1-9 yr may be needed); max 16 mg/kg (400 mg) per day in patients with risk factors for decreased theophylline clearance or who cannot receive recommended serum concentration monitoring; NIH recommends initial dose for asthma of 10 mg/kg/day (max 300 mg/day) titrated to serum concentration of 5-15 mcg/ml (usual max 800 mg/day in patients ≥12 yr and 16 mg/kg/day in children 1-11 yr)
• Neonate/infant ≤52 wk:
PO
Calculate initial dose using the following equation: [(0.2 × age in wks) + 5] × (kg body weight) = theophylline dosage in mg/day; in infants ≤26 wk, divide dose and administer q8hr and in infant >26 wk, divide dose and give q6hr; adjust dose to maintain a steady-state serum concentration of 5-10 mcg/ml in neonates and 10-15 mcg/ml in infants; NIH recommends initial dose for asthma of 10 mg/kg/day titrated to theophylline serum concentration of 5-15 mcg/ml, max in mg/kg/day = [(0.2 × age in weeks) + 5]
•
Extended-release products are to be used only for chronic disease management; do not use in treatment of acute symptoms of asthma and reversible bronchospasm
• Adult/adolescents/child ≥12 yr and >45 kg:
(Theo-24 Cap) PO
Initially, 300-400 mg/day q24hr; evening dosing is not recommended; after 3 days, if tolerated, increase to 400-600 mg/day q24hr; adjust dose to maintain therapeutic range; doses of 400-1600 mg/day may be needed; max 400 mg/day in patients with decreased theophylline clearance, (elderly >60 yr), and in those who cannot receive recommended serum concentration monitoring
• Child >12 yr/adolescent <16 yr and <45 kg:
(Theo-24 Cap) PO
Initially, 12-14 mg/kg (max 300 mg) per day q24hr; evening dosing is not recommended; after 3 days, if tolerated, may increase to 16 mg/kg (max 400 mg) per day; after 3 more days, if tolerated and if needed, increase to 20 mg/kg (max 600 mg) per day; adjust dose to maintain therapeutic range; max 16 mg/kg/day up to 400 mg/day in patients with decreased theophylline clearance
• Adult/adolescents/child ≥3 yr:
IV
2.5 mg/kg over 45-60 min
Available forms:
Inj 250 mg/10 ml, 500 mg/20 ml, 100 mg/100 ml in 0.45% NaCl, 200 mg/100 ml in 0.45% NaCl; rect supp 250, 500 mg; tabs 100, 200 mg; ext rel tab 100, 200, 300, 400, 450, 600 mg; ext rel cap 100, 200, 300, 400; elixir 80 mg/15 ml
•
Avoid IM inj; pain and tissue damage may occur
•
Avoid giving with food
•
Only clear sol; flush IV line before dose
•
May be
diluted
for IV inf in 100-200 ml in D
5
W, D
10
W, D
20
W, 0.9% NaCl, 0.45% NaCl, LR
•
Give
loading dose over 1/2 hr; max rate of inf 25 mg/min, use inf pump; after loading dose, give by cont inf
Syringe compatibilities:
Heparin, metoclopramide, PENTobarbital, thiopental
Y-site compatibilities:
Allopurinol, amifostine, amphotericin B, amrinone, aztreonam, cefTAZidime, cholesteryl sulfate complex, cimetidine, cladribine, DOXOrubicin liposome, enalaprilat, esmolol, famotidine, filgrastim, fluconazole, fludarabine, foscarnet, gallium, granisetron, heparin sodium with hydrocortisone sodium succinate, labetalol, melphalan, meropenem, netilmicin, PACLitaxel, pancuronium, piperacillin/tazobactam, potassium chloride, propofol, ranitidine, remifentanil, sargramostim, tacrolimus, teniposide, thiotepa, tolazoline, vecuronium
CNS:
Anxiety, restlessness, insomnia,
dizziness
,
seizures,
headache, light-headedness, muscle twitching, tremors
CV:
Palpitations, sinus tachycardia
, hypotension, flushing,
dysrhythmias,
edema
GI:
Nausea, vomiting
, diarrhea, dyspepsia, anal irritation (suppositories), epigastric pain, reflux, anorexia
GU:
Urinary frequency, SIADH
INTEG:
Flushing, urticaria
MISC:
Hyperglycemia
RESP:
Tachypnea, increased respiratory rate
Metabolized by liver (caffeine); excreted in urine; crosses placenta; appears in breast milk; half-life 6.5-10.5 hr; half-life increased in geriatric patients, hepatic disease, CHF, neonates, premature infants; protein binding 40%, crosses into CSF
PO:
Onset 1/4 hr, peak 1-2 hr, duration 6-8 hr, well absorbed
PO-ER:
Onset unknown, peak 4-7 hr, duration 8-12 hr, well absorbed slowly
IV:
Onset rapid, duration 6-8 hr
RECT:
Onset erratic, peak 1-2 hr, duration 6-8 hr, supp absorbed erratically, sol absorbed quickly
•
Dose-dependent reversal of neuromuscular blockade
•
Dysrhythmias: halothane
•
May increase or decrease theophylline levels: carBAMazepine, loop diuretics, isoniazid
Increase:
action of theophylline, toxicity—cimetidine, nonselective β-blockers, erythromycin, clarithromycin, oral contraceptives, corticosteroids, interferons, fluoroquinolones, disulfiram, mexiletine, fluvoxaMINE, high doses of allopurinol, influenza vaccines, interferon, benzodiazepines
Increase:
adverse reactions—tetracyclines
Increase:
elimination—smoking
Decrease:
effects of lithium
Decrease:
effect of theophylline—nicotine products, adrenergics, barbiturates, phenytoin, ketoconazole, rifampin
Increase:
effects—cola tree, guarana, yerba maté, tea (black, green), horsetail, ginseng, Siberian ginseng
Decrease:
effects—St. John’s wort
Increase:
effect—xanthines
Increase:
elimination by low-carbohydrate, high-protein diet; charcoal-broiled beef
Decrease:
elimination by high-carbohydrate, low-protein diet
Increase:
plasma-free fatty acids
•
Theophylline blood levels (therapeutic level is 10-20 mcg/ml); toxicity may occur with small increase above 20 mcg/ml, especially in geriatric patients; whether theophylline was given recently (24 hr)
•
Monitor I&O; diuresis occurs; dehydration may occur in geriatric patients or children
•
Liver function tests: periodically, lower doses may be required in those with moderate to severe hepatic disease
•
Respiratory rate, rhythm, depth; auscultate lung fields bilaterally; notify prescriber of abnormalities, monitor pulmonary function tests
•
Allergic reactions: rash, urticaria; if these occur, product should be discontinued
•
Storage of diluted sol for 24 hr if refrigerated
•
Therapeutic response: decreased dyspnea, respiratory stimulation for infants, clear lung fields bilaterally
•
To take doses as prescribed, not to skip dose, not to double dose
•
To check OTC medications, current prescription medications for ePHEDrine; will increase CNS stimulation; not to drink alcohol or caffeine products (tea, coffee, chocolate, colas); to avoid large amounts of charcoal-grilled beef
•
To avoid hazardous activities; dizziness may occur
•
If GI upset occurs, to take product with 8 oz water; to avoid food because absorption may be decreased
To notify prescriber immediately about
toxicity:
insomnia, anxiety, nausea, vomiting, rapid pulse, seizures, flushing, headache, diarrhea
•
To notify prescriber about changes in smoking habits because a change in dose may be required; to avoid smoking because it decreases drug blood levels and terminal half-life
•
To increase fluids to 2 L/day to decrease secretion viscosity