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Oxtriphylline Side Effects

Applies to oxtriphylline: oral delayed release tablet, oral tablet extended release.


Do not crush or chew any extended-release formulation of oxtriphylline. Swallow the medication whole. It is specially formulated to release slowly in your body. If you do not know whether your medication is an extended-release formulation, ask your pharmacist.

Call your doctor right away if you experience nausea, vomiting, insomnia, restlessness, seizures, an increased heart rate, or a headache. These could be signs of too much oxtriphylline in your blood.

Do not start or stop smoking without your doctor’s knowledge. Smoking may affect your dosage.

Do not take more of this medicine than is prescribed without consulting your doctor. Seek medical attention if you are having increasing difficulty breathing.

If you experience any of the following serious side effects, stop taking oxtriphylline and seek emergency medical attention:

Other, less serious side effects may occur although they are not common at appropriate doses. Continue to take oxtriphylline and talk to your doctor if you experience

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

For Healthcare Professionals

Applies to oxtriphylline: oral delayed release tablet, oral tablet extended release.


Most of the adverse effects of oxtriphylline, the choline salt of theophylline, have been dependent on the serum concentration. Generally, serum concentrations of theophylline ranging from 10 to 20 mcg/mL are considered therapeutic, and serum concentrations greater than 20 mcg/mL are associated with greater toxicity.[Ref]

There are several factors which may predispose a patient to higher serum concentrations and, thus, toxicity. These factors may include increased age, concomitant drugs which reduce the clearance of theophylline, hypothyroidism, congestive heart failure, liver disease, renal failure, and alterations in smoking habits. One series of patients with theophylline intoxication had recent upper respiratory tract infections.

The nature of acute toxicity of theophylline differs from chronic toxicity. Acute overdose is associated with higher theophylline concentrations and younger patients. In acute overdose the severity of toxicity is correlated with peak serum concentrations. Chronic overdosage is seen more commonly in older patients, and severe toxicity may occur with serum concentrations which are much lower than those seen in acute toxicity. In these patients, increased age is a predictor of severe toxicity.[Ref]


Gastrointestinal side effects have included anorexia, nausea, vomiting, and abdominal pain. Oxtriphylline may also cause locally-mediated gastrointestinal upset.[Ref]

Nervous system

Nervous system side effects have included generalized seizures, most commonly in patients with elevated serum concentrations, although seizures have occurred at therapeutic concentrations. Theophylline may also cause nervousness and tremor at therapeutic dosages, which become worse as serum concentrations increase.[Ref]

The mechanism of theophylline-induced seizures has not been determined. Seizures are generally focal with secondary generalization. Permanent neurologic deficits have been reported and morbidity may be high, especially in the elderly, patients with severe underlying disease, and patients with prolonged, uncontrolled seizure activity. The onset of seizures is not always preceded by less severe symptoms of theophylline toxicity. Patients with an abnormal neurologic history, including a history of seizures, cerebral infarct, or head trauma, may be predisposed to seizure activity. If theophylline is used in these types of patients, serum concentrations should be monitored closely and maintained in the low therapeutic range.[Ref]


Cardiovascular side effects have included increased heart rate which has progressed to atrial tachycardia or ventricular tachycardia. Patients with a history of arrhythmias may be predisposed to this effect. Hypotension has occurred with rapid intravenous administration.[Ref]

Theophylline serum concentrations are a significant predictor of arrhythmias. One study reported multifocal atrial tachycardia in 8% and 16% of patients with a serum concentration between 10 and 20 mcg/mL and greater than 20 mcg/mL, respectively. The onset of serious arrhythmias is not always preceded by less severe signs of theophylline toxicity.[Ref]


Metabolic side effects have included hypokalemia, hyperglycemia, respiratory alkalosis, hypophosphatemia, and hypomagnesemia. The magnitude of these abnormalities have been correlated with theophylline concentrations.[Ref]

In one group of patients with theophylline concentrations greater than 20 mcg/mL, hyperglycemia has present in approximately 50%, hypokalemia in 15%, and hypomagnesemia in 20%. Hyponatremia and hypophosphatemia were seen less frequently.[Ref]


Genitourinary side effects have included rare reports of urinary retention.[Ref]


1. Sessler CN (1990) "Theophylline toxicity: clinical features of 116 consecutive cases." Am J Med, 88, p. 567-76

2. Schiff GD, Hegde HK, LaCloche L, Hryhorczuk DO (1991) "Inpatient theophylline toxicity: preventable factors." Ann Intern Med, 114, p. 748-53

3. Aderka D, Shavit G, Garfinkel D, et al. (1983) "Life-threatening theophylline intoxication in a hypothyroid patient." Respiration, 44, p. 77-80

4. Covelli HD, Knodel AR, Heppner BT (1985) "Predisposing factors to apparent theophylline-induced seizures." Ann Allergy, 54, p. 411-5

5. Milgrom H, Bender B (1993) "Current issues in the use of theophylline." Am Rev Respir Dis, 147, s33-9

6. Shannon M (1993) "Predictors of major toxicity after theophylline overdose." Ann Intern Med, 119, p. 1161-7

7. (2001) "Product Information. Theo-Dur (theophylline)." Schering Corporation

8. Stoller JL (1985) "Oesophageal ulceration and theophylline." Lancet, 2, p. 328-9

9. Nakada T, Kwee IL, Lerner AM, Remler MP (1983) "Theophylline-induced seizures: clinical and pathophysiologic aspects." West J Med, 138, p. 371-4

10. Hall RC, Beresford TP, Stickney SK, et al. (1985) "Psychiatric reactions produced by respiratory drugs." Psychosomatics, 26, 605-8,615-6

11. Bahls FH, Ma KK, Bird TD (1991) "Theophylline-associated seizures with "therapeutic" or low toxic serum concentrations: risk factors for serious outcome in adults." Neurology, 41, p. 1309-12

12. Marchlinski FE, Miller JM (1985) "Atrial arrhythmias exacerbated by theophylline: response to verapamil and evidence for triggered activity in man." Chest, 88, p. 931-4

13. Levine JH, Michael JR, Guarnieri T (1985) "Multifocal atrial tachycardia: a toxic effect of theophylline." Lancet, 1, p. 12-4

14. Taniguchi A, Ohe T, Shimorura K (1989) "Theophylline-induced ventricular tachycardia in a patient with chronic lung disease: sensitivity to verapamil." Chest, 96, p. 958-9

15. Bittar G, Friedman HS (1991) "The arrhythmogenicity of theophylline: a multivariate analysis of clinical determinants." Chest, 99, p. 1415-20

16. Flack JM, Ryder KW, Strickland D, Whang R (1994) "Metabolic correlates of theophylline therapy: a concentration-related phenomenon." Ann Pharmacother, 28, p. 175-9

17. Hagley MT, Traeger SM, Schuckman H (1994) "Pronounced metabolic response to modest theophylline overdose." Ann Pharmacother, 28, p. 195-6

18. Hall KW, Dobson KE, Dalton JG, Ghignone MC, Penner SB (1984) "Metabolic abnormalites associated with intentional theophylline overdose." Ann Intern Med, 101, p. 457-62

19. Prakash M, Washburne JD (1981) "Theophylline and urinary retention." Ann Intern Med, 94, p. 823

20. Clark BG, Vestal RE (1984) "Adverse drug reactions in the elderly: case studies." Geriatrics, 39, 53-4,60-3,66

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.