Aminophylline intravenous

Administration - The loading dose of aminophylline can be given by very slow IV push or, more conveniently, may be infused in a small guantity (usually 100 to 200 mL) of 5% Dextrose Injection or 0.9% Sodium Chloride Injection. Do not exceed the rate of 25 mg/min. Thereafter, maintenance therapy can be administered by a large volume infusion to deliver the desired amount of drug each hour. Aminophylline is compatible with most commonly used IV solutions. Oral therapy should be substituted for intravenous aminophylline as soon as adeguate improvement is achieved. 

The intravenous administration of aminophylline (or theophylline) may present some problems if the drug is given too rapidly. In such cases, severe headache, hypotension, and palpitation accompany drug administration. Subsequently the patient may show signs of excessive CNS stimulation, shock, and even death. Children appear to be especially prone to this toxicity. 

Mitra A, Bassler D, Goodman K, et al. Intravenous aminophylline for acute severe asthma in children over two years receiving inhaled bronchodilators. Cochrane Database Syst Rev. 2005 CD001276. 

Aminophylline (theophylline ethylenediamine), given intravenously, is used in patients with status asthmaticus who do not respond to epinephrine. In addition, epinephrine may be administered subcutaneously for acute asthma attacks. Epinephrine may also be given along with theophylline. It is thought that the bronchodilation is associated with me enhanced concentration of cyclic AMP, which is metabolized according to the following sequence ... 

The treatment of acute attacks of asthma in patients reporting to the hospital requires more continuous assessment and repeated objective measurement of lung function. For patients with mild attacks, inhalation of a -receptor agonist is as effective as subcutaneous injection of epinephrine. Both of these treatments are more effective than intravenous administration of aminophylline. 

Aminophylline is used in the treatment of asthma (as a bronchodilator) and in chronic obstructive pulmonary disease. In acute bronchospasm, aminophylline should not be given by the intravenous route the oral route is preferred. Parenteral administration can cause pain and is not recommended. Aminophylline is used as a cosmetic to remove fat from the thigh.45... 

Warfarin sodium may be adsorbed to PVC and intravenous infusion sets but may be minimized with glass containers or polyethylene-lined containers. Warfarin sodium is incompatible with solutions of adrenaline hydrochloride, amikacin sulfate, metaraminol tartrate, oxytocin, promazine hydrochloride, tetracycline hydrochloride, aminophylline, bretylium tosylate, ceftazidime, cimetidine hydrochloride, ciprofloxacin lactate, dobutamine hydrochloride, esmolol hydrochloride, gentamicin sulfate, labetalol hydrochloride, metronidazole hydrochloride, and vancomycin hydrochloride.130131... 

M.A. Parrish, et al., Stability of ceftriaxone sodium and aminophylline or theophylline in intravenous admixtures. Am. J. Hosp. Pharmacol. 51 92-94, 1994. 

Intravenous aminophylline is used in patients with a poor response to initial therapy levels must be measured. 

A 3-year-old boy comes into A E with a severe asthma attack. This is his third in the last three months. He is started on nebulised salbutamol, intravenous aminophylline and oral prednisolone. The presenting symptoms include ... 

Toxicity. The estimated minimum lethal dose after intravenous administration is 0.1 g fatalities have occurred after oral doses of 8.4 mg/kg in a child and after 25 to 100 mg/kg of aminophylline given as a suppository. Recovery has been reported after ingestion of choline theophyllinate equivalent to 12.8 g of theophylline. Toxic effects are usually associated with plasma concentrations greater than 30 pg/ml and fatalities with concentrations above 50pg/ml premature neonates appear to be relatively resistant to theophylline poisoning. 

A 20-year-old man is hospitalized after an asthmatic attack precipitated by an upper respiratory infection and fails to respond in the emergency room to two subcutaneously injected doses of epinephrine. The patient has not been taking theophylline-containing medications for the past 6 weeks. He weighs 60 kg and you estimate that his apparent volume of theophylline distribution is 0.45 L/kg. Bronchodilator therapy includes a 5.6-mg/kg loading dose of aminophylline, infused intravenously over 20 min, followed by a maintenance infusion of 0.63 mg/kg per hour (0.50 mg/kg per hour of theophylline). Forty-eight hours later, the patient s respiratory status has improved. However, he has nausea and tachycardia, and his plasma theophylline level is 24 xg/mL. 

FIGURE 22.7 Kinetic analysis of theophylline plasma ( ) and milk (a) concentrations after intravenous administration of a 3.2- to 5.3-mg/kg aminophylline dose. The lines represent the least-squares fit of the measured concentrations. The interval and volume of each milk collection are shown by the solid bars. The milligram recovery of theophylline in each breast-milk collection is shown by the numbers above the bars. (Reproduced with permission from Stec GP et al. Clin Pharmacol Ther 1980 28 404-8.)... 

A patient with aorto-iliac occlusive vascular disease and hypertension suffered a stroke 6.5 minutes after administration of intravenous dipyridamole during a thallium myocardial study (11). Aminophylline did not reverse its progression. 

The practicability of dipyridamole A-ammonia myocardial positron emission tomography for perioperative risk assessment of coronary artery disease in patients with severe chronic obstructive pulmonary disease undergoing lung volume reduction surgery has been studied in 13 men and 7 women (mean age 57 years) without symptoms of coronary artery disease (12). Nine patients had intolerable dyspnea due to bronchoconstriction and required intravenous aminophylline. Dipyridamole cannot be recommended as a pharmacological stress in this setting. 

The third infant was given aminophylline orally and doxapram by intravenous infusion 5 days later cisapride was added to treat suspected gastro-esophageal reflux. The next day the infant had developed second-degree AV block, with a prolonged QT interval. Doxapram was withdrawn and sinus rhythm returned 36 hours later. 

A 30-year-old woman developed a generalized urticarial reaction immediately after the intravenous administration of aminophylline (4). Skin intradermal testing was positive to ethylenediamine. Rechallenge was positive with intravenous aminophylline but negative with diprophylline, which does not contain ethylenediamine. 

An 8-year-old boy with status asthmaticus was given intravenous aminophylline and then switched to mod-ified-release oral theophylline on day 3, when his serum theophylline concentration was 15 pg/ml. On day 4 he was given a single dose of pyrantel 160 mg (for A. lumbricoides infection) at the same time as his second oral dose of theophylline. About 2.5 hours later his serum theophylline concentration was 24 pg/ml, and a further 1.5 hours later it had risen to 30 pg/ml. No further theophylline was given and no theophyUine toxicity occurred. 

Chaithiraphan S. Fatal complication associated with intravenous use of aminophylline. J Med Assoc Thai 1976 59(ll) 507-9. 

Adults After cyanosis is overcome, atropine sulfate should be used, 2 mg i.v. Doses should be repeated at 5-10 min intervals until signs of atropin-ization appear. This should be maintained for 24 h or longer if necessary. 2-PAM (pralidoxime chloride) should be given. Adult dose 1 g, slowly, intravenously. Contraindicated are morphine, aminophylline, theophylline, phenothiazine tranquilizers, and barbiturates. 

Ingestion of sustained-release products is the most common route of both accidental and intentional exposure to theophylline. Theophylline is available in oral and intravenous dosage forms. Aminophylline is available in oral, rectal, and intravenous dosage forms. 

Continuous intravenous infusions of theophylline (or its salt, aminophylline) can be individualized rapidly by determining the... 

In vitro studies with gentamicin and aminophylline have shown that the delivery of these drugs may be delayed substantially depending on the flow rate and injection site. These observations were confirmed with infusion of chloramphenicol succinate and tobramycin. These studies clearly have demonstrated that the variables of intravenous drug infusion systems (e.g., flow rate. 

Magnesium sulfate is a moderately potent bronchodilator that is similar to aminophylline, producing relaxation of smooth muscle and central nervous system depression. The use of intravenous magnesium sulfate in patients presenting to the emergency department is... 

A number of other agents may be required for the treatment of anaphylactic reactions. Corticosteroids (hydrocortisone sodium succinate intravenously) are recommended to reduce the risk of late-phase reactions. Aminophylline may be used as adjunctive therapy for bronchospasm. Histamine (Hi) receptor blockers (such as diphenhydramine) may be administered to reduce some of the symptoms associated with anaphylaxis however, these agents are not effective as primary therapy. 

If bronchospasm is present, administer aminophylline 6 mg/kg intravenously over 20 min. 

Formulations of xanthines include intravenous injection, tablets and capsules. Examples of xanthine bronchodilators are theophylline and aminophylline. 

Although asthma is considered to be a reversible condition, severe acute attacks can cause obstruction that can take days to reverse and in some cases is not reversible at all. Such attacks need to be treated as a medical emergency requiring hospital treatment. Treatment includes oxygen, inhalation of salbutamol in oxygen, intravenous hydrocortisone and oral prednisolone. Sometimes inhaled antimuscarinics are also used and intravenous salbutamol and aminophylline plus antibiotics if there is infection as well. 

The methylxanthines consist of aminophylline, dyphyl-line, enprofylline, and pentoxifylline. Aminophylline (theophylline ethylenediamine) is the most widely used of the soluble theophyllines. Its main therapeutic effect is bronchodilation. In addition, it causes CNS stimulation, cardiac acceleration, diuresis, and gastric secretion. Aminophylline is available in an oral, rectal (pediatric), or intravenous solution, which is used in the treatment of status asthmaticus. Although it is a less effective bronchodilator than beta-adrenergic agonists, it is particularly useful in preventing nocturnal asthma (see also Figure 94). 

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