Spasmolytic, bronchodilatorUS FDA Database Verified

theophylline (Rx)

Generic: Theophylline

Brand: Elixophyllin, Theo-24, Theochron, Uniphyl

(thee-off'i-lin)

Pregnancy Category: C

Pharmacological Action

Relaxes smooth muscle of respiratory system by blocking phosphodiesterase, which increases cyclic AMP, exact action unknown

Therapeutic outcome: Ability to breathe without difficulty

Uses

Bronchial asthma, bronchospasm of COPD, chronic bronchitis, emphysema

Contraindications

Hypersensitivity to xanthines, tachydysrhythmias

Precautions: Pregnancy C, children, geriatric, CHF, cor pulmonale, hepatic disease, active peptic ulcer disease, diabetes mellitus, hyperthyroidism, hypertension, seizure disorder

Dosage & Routes

Acute exacerbations of reversible airway obstructions

Adult: PO/IV 5 mg/kg loading dose over 20-30 min COPD, chronic bronchitis

Adult: IV 0.4 mg/kg/hr in nonsmokers or 0.7 mg/kg/hr in smokers Adult, child >45 kg: Maintenance PO (regular release) 10 mg/kg/day, in divided doses q1-8 hr; after 3 days increase dosage to 400 mg in divided doses q6-8 hr; after 3 more days increase to 600 mg in divided doses q6-8 hr; max 800 mg/day Apnea of prematurity

Neonate: IV 4 mg/kg over 20-30 min, then maintenance IV/PO neonate ≥24 days 1.5 mg/kg q12 h

Available forms: Cap, ext rel 100, 200, 300, 400 mg; tab ext rel 100, 200, 400, 450, 600 mg; elixir 80 mg/15 ml; sol for inj 250 mg/10 ml, 500 mg/20 ml

Implementation PO route - Do not crush or chew time release products - Contents of bead-filled cap may be sprinkled over food for children's use - Give PO with 8 oz water; to decrease GI symptoms; avoid food, absorption may be affected - Store diluted sol for 24 hr if refrigerated IV route - Give loading dose over 20-30 min; max 20-25 mg/min; do not give by rapid IV; use only by cont inf

Y-site compatibilities: Acyclovir, ampicillin, aztreonam, ceFAZolin, cefoTEtan, cefTAZidime, cefTRIAXone, cimetidine, clindamycin, dexamethasone, diltiazem, DOBUTamine, DOPamine, doxycycline, erythromycin, famotidine, fluconazole, gentamicin, haloperidol, heparin, hydrocortisone, lidocaine, methyldopate, methylPREDNISolone, metroNIDAZOLE, midazolam, nafcillin, nitroglycerin, nitroprusside, penicillin G potassium, piperacillin, potassium chloride, ranitidine, ticarcillin, ticarcillin/clavulanate, tobramycin, vancomycin

Adverse Effects

CNS: Anxiety, restlessness, insomnia, dizziness, seizures, headache, light-headedness, muscle twitching, tremors

CV: Palpitations, sinus tachycardia, hypotension, dysrhythmias, fluid retention with tachycardia

ENDO: Hyperglycemia

GI: Nausea, vomiting, anorexia, diarrhea, bitter taste, dyspepsia, gastric distress

INTEG: Flushing, urticaria

MISC: SIADH, urinary frequency

RESP: Increased rate, tachypnea

Pharmacokinetics

Absorption: Well absorbed (PO), slowly absorbed (ext rel)

Distribution: Crosses placenta, widely distributed

Metabolism: Liver

Excretion: Kidneys, breast milk

Half-life: 6.5-10.5 hr; increased in liver disease, CHF, geriatric

Pharmacodynamics

PO: Onset Rapid, Peak 1 hr, Duration 6 hr PO–TIME

REL: Onset Slow, Peak 4-8 hr, Duration 12-24 hr

IV: Onset Immediate, Peak Inf end, Duration 6-8 hr

Interactions

Individual drugs

CarBAMazepine: decreased theophylline level Cimetidine, disulfiram, erythromycin, fluvoxaMINE, influenza vaccine, mexiletine, propranolol: increased theophylline action

Lithium: decreased effect of lithium PHENobarbital, phenytoin, rifampin: decreased theophylline

Drug classifications

Anticoagulants: increased anticoagulant level b-Adrenergic blockers: cardiotoxicity Contraceptives (oral), corticosteroids, fluoroquinolones, interferons: increased theophylline action

Smoking: decreased theophylline level

Drug/herb Coffee, cola nut, guarana, ma huang (ephedra), tea (black, green), yerba maté: increased toxicity St. John's wort: decreased theophylline level

Nursing Considerations

Assessment - Monitor theophylline blood levels (therapeutic level is 5-15 mcg/ml); toxicity may occur with small increase above 15 mcg/ml - Monitor I&O; diuresis occurs; dehydration may result in children or geriatric - Assess for signs of toxicity: irritability, insomnia, restlessness, tremors, nausea, vomiting - Monitor respiratory rate, rhythm, depth; auscultate lung fields bilaterally; notify prescriber of abnormalities - Assess for allergic reactions: rash, urticaria; if these occur, product should be discontinued

Patient/family education - Advise patient to check OTC medications, current prescription medications for ePHEDrine, which increases stimulation, and to avoid alcohol, caffeine - Caution patient to avoid hazardous activities; dizziness may occur - Inform patient that if GI upset occurs, to take product with 8 oz of water; avoid food; absorption may be decreased - Advise patient to notify prescriber of toxicity: nausea, vomiting, anxiety, insomnia, seizures - Advise patient to notify prescriber of change in smoking habit; dosage may have to be changed

Evaluation

Positive therapeutic outcome: Ability to breathe more easily

Reference

Mosby's Drug Guide; Davis Drug Guide

Need clinical tools for this drug?

Save notes, bookmark this drug, and run formula method (desire over have) dosage calculations all inside the KosPharm Dashboard.

One-time payment. No subscription. No recurring charges.