Aminophylline; Theophylline Ethylenediamine
Aminophylline (theophylline ethylenediamine)
Brand Name: Truphylline
Pregnancy Category C
Drug classes: Bronchodilator, Xanthine
Relaxes bronchial smooth muscle, causing bronchodilation and increasing vital capacity, which has been impaired by bronchospasm and air trapping; in higher concentrations, it also inhibits the release of slow-reacting substance of anaphylaxis (SRS-A) and histamine.
· Symptomatic relief or prevention of bronchial asthma and reversible bronchospasm associated with chronic bronchitis and emphysema
· Unlabeled uses: respiratory stimulant in Cheyne-Stokes respiration; treatment of apnea and bradycardia in premature babies
· Contraindicated with hypersensitivity to any xanthine or to ethylenediamine, peptic ulcer, active gastritis; rectal or colonic irritation or infection (use rectal preparations).
Irritability (especially children); restlessness, dizziness, muscle twitching, convulsions, severe depression, stammering speech; abnormal behavior characterized by withdrawal, mutism, and unresponsiveness alternating with hyperactive periods, Palpitations, sinus tachycardia, ventricular tachycardia, life-threatening ventricular arrhythmias, circulatory failure, Loss of appetite, hematemesis, epigastric pain, gastroesophageal reflux during sleep, increased AST, Proteinuria, increased excretion of renal tubular cells and RBCs; diuresis (dehydration), urinary retention in men with prostate enlargement, Tachypnea, respiratory arrest, Fever, flushing, hyperglycemia, SIADH, rash
· Increased effects with cimetidine, erythromycin, troleandomycin, clindamycin, lincomycin, influenza virus vaccine, oral contraceptives
· Possibly increased effects with thiabendazole, rifampin, allopurinol
· Increased cardiac toxicity with halothane; increased likelihood of seizures when given with ketamine; increased likelihood of adverse GI effects when given with tetracyclines
· Increased or decreased effects with furosemide, levothyroxine, liothyronine, liotrix, thyroglobulin, thyroid hormones
· Decreased effects in patients who are cigarette smokers (1–2 packs per day); theophylline dosage may need to be increased 50%–100%
· Decreased effects with phenobarbital, aminoglutethimide
· Increased effects, toxicity of sympathomimetics (especially ephedrine) with theophylline preparations
· Decreased effects of phenytoin and theophylline preparations when given concomitantly
· Decreased effects of lithium carbonate, nondepolarizing neuromuscular blockers given with theophylline preparations
· Mutually antagonistic effects of beta-blockers and theophylline preparations
Interaction with Food:
· Elimination is increased by a low-carbohydrate, high-protein diet and by charcoal broiled beef
· Elimination is decreased by a high-carbohydrate, low-protein diet
· Food may alter bioavailability and absorption of timed-release theophylline preparations, causing toxicity. These forms should be taken on an empty stomach
Interaction with lab test
· Interference with spectrophotometric determinations of serum theophylline levels by furosemide, phenylbutazone, probenecid, theobromine; coffee, tea, cola beverages, chocolate, acetaminophen cause falsely high values
· Alteration in assays of uric acid, urinary catecholamines, plasma free fatty acids by theophylline preparations
· Administer to pregnant patients only when clearly needed--neonatal tachycardia, jitteriness, and withdrawal apnea observed when mothers received xanthines up until delivery.
· Caution patient not to chew or crush enteric-coated timed-release forms.
· Give immediate-release, liquid dosage forms with food if GI effects occur.
· Do not give timed-release forms with food; these should be given on an empty stomach 1 hr before or 2 hr after meals.
· Maintain adequate hydration.
· Monitor results of serum theophylline levels carefully, and arrange for reduced dosage if serum levels exceed therapeutic range of 10–20 mcg/mL.
· Take serum samples to determine peak theophylline concentration drawn 15–30 min after an IV loading dose.
· Monitor for clinical signs of adverse effects, particularly if serum theophylline levels are not available.
· Maintain diazepam on standby to treat seizures.