Theophylline

Interconversion between caffeine and theophylline has been reported in preterm neonates. Concurrent use is not recommended.

Concomitant use may lower the seizure threshold. Do not co-administer with ketamine hydrochloride.

Co-administration with theophylline is contraindicated because of hypotension.

Cimetidine reduces hepatic metabolism of theophylline, increasing blood levels. Adverse clinical effects reported. Alteration less pronounced with 800 mg bedtime dosing. Appropriate monitoring recommended.

Cimetidine reduces hepatic metabolism of theophylline, increasing blood levels. Adverse clinical effects reported; monitoring recommended regardless of cimetidine dosing.

Concurrent administration may result in increased risk of CNS or other adverse reactions due to increased plasma exposure and prolonged levels.

Concurrent administration may result in increased risk of CNS or other adverse reactions due to increased plasma exposure and prolonged levels.

Concurrent administration may result in increased risk of CNS or other adverse reactions due to increased plasma exposure and prolonged levels.

Avoid concomitant use as deferasirox increases theophylline levels, potentially causing CNS or other serious adverse reactions.

Theophylline may abolish the coronary vasodilation induced by intravenous dipyridamole, potentially leading to false negative thallium imaging results.

Erythromycin may increase serum theophylline levels, potentially causing toxicity. Concomitant theophylline may decrease erythromycin concentrations by approximately 35%, resulting in subtherapeutic erythromycin levels.

Erythromycin may increase serum theophylline levels, potentially causing toxicity. Theophylline may decrease erythromycin concentrations by ~35%, resulting in subtherapeutic erythromycin levels.

May increase serum theophylline levels and cause potential toxicity. Concomitant use may also decrease erythromycin serum concentrations.

Concurrent isoniazid and theophylline administration may cause elevated plasma theophylline levels. Close monitoring and dosage adjustment recommended due to theophylline's narrow therapeutic range.

Inhibits airway response to methacholine chloride; hold for 12-48 hours before testing.

Methotrexate increases theophylline plasma concentrations, increasing risk of theophylline adverse reactions. Monitor theophylline levels and adjust dosage accordingly.

Concurrent use may lead to significantly increased plasma theophylline levels (mean 72% increase). Theophylline blood level monitoring recommended when used concurrently with mexiletine.

Nilutamide inhibits cytochrome P-450 isoenzymes, reducing metabolism of theophylline and increasing serum half-life, potentially leading to toxic levels. Dosage may need modification.

Ofloxacin may prolong theophylline half-life, elevate serum levels, and increase risk of adverse reactions including seizures. Theophylline levels should be closely monitored and dosage adjusted accordingly.

Concomitant administration leads to increased theophylline levels and theophylline toxicity in some individuals. Monitoring of theophylline levels recommended.

Zileuton significantly decreases theophylline clearance (~50%), doubling AUC and increasing Cmax by 73%. Theophylline-related adverse reactions occur more frequently. Reduce theophylline dose by approximately one-half and monitor plasma concentrations.

Monitoring of drug concentration recommended upon initiation or discontinuation of HUMIRA; dose adjustment may be needed.

ADALIMUMAB-AACF may influence CYP450 enzyme formation, affecting theophylline metabolism. Monitoring of theophylline concentration is recommended upon initiation or discontinuation of ADALIMUMAB-AACF.

Adalimumab may influence CYP450 enzyme formation. Monitoring of drug concentration and dose adjustment recommended.

Adalimumab-adaz may suppress CYP450 enzyme formation, potentially affecting theophylline concentration. Monitoring and dose adjustment recommended.

CYP450 enzyme formation may be suppressed by adalimumab-adbm. Monitoring of drug concentration recommended upon initiation or discontinuation.

Adalimumab may influence CYP450 enzyme formation, affecting theophylline concentration. Monitoring of drug concentration and dose adjustment recommended.

YUSIMRY may suppress CYP450 enzyme formation; monitor theophylline concentration and adjust dose as needed upon initiation or discontinuation.

AMJEVITA may influence CYP450 enzyme formation; monitoring of theophylline concentration and dose adjustment recommended.

HADLIMA may influence CYP450 enzyme formation; monitoring of theophylline concentration recommended with dose adjustment as needed.

Adalimumab-fkjp may influence CYP450 enzyme formation; monitoring of theophylline concentration recommended with dose adjustment as needed.

Adalimumab-ryvk may suppress CYP450 enzyme formation, affecting theophylline concentration. Monitor concentration and adjust dose as needed.

Theophylline blocks adenosine receptors, potentially reducing adenosine's therapeutic effects.

Albendazole induces cytochrome P450 1A; monitoring of plasma concentrations of theophylline is recommended during and after albendazole treatment.

A single large dose of alcohol decreases theophylline clearance for up to 24 hours, resulting in approximately 30% increase in serum concentration.

Allopurinol at doses ≥600 mg/day decreases theophylline clearance, resulting in approximately 25% increase in serum concentration.

Aminoglutethimide increases theophylline clearance.

Anagrelide may increase theophylline exposure as a CYP1A2 substrate; monitor for theophylline toxicity.

Limited CYP1A2 inhibitory activity may alter theophylline exposure; monitor accordingly.

Xanthine derivative may potentiate hypokalemia. Concomitant use associated with increased heart rate (2-3 bpm) and systolic blood pressure (6-8 mm Hg). Use with caution.

Increases in exposure may be observed as cannabidiol is a weak CYP1A2 inhibitor. Consider dosage reduction where minimal concentration changes may lead to serious adverse reactions.

CYP3A4 inducer that decreases carbamazepine plasma levels. Carbamazepine levels and/or dosage adjustment may be necessary.

Clarithromycin increases serum theophylline concentrations by approximately 20%. Monitoring of serum theophylline concentrations should be considered.

Oral contraceptives may inhibit metabolism of theophylline, increasing its plasma concentrations.

Possible interaction with ropivacaine through CYP1A2 competitive inhibition.

CYP3A4 substrate; diazepam may interfere with its metabolism, leading to potential drug-drug interaction.

Increased risk of hypokalemia with coadministration of dichlorphenamide and theophylline.

Interaction may manifest as increased skeletal muscle activity, agitation, and hyperactivity when combined with doxapram.

Concomitant use may increase frequency of nausea, nervousness, and insomnia. Monitor patient and manage symptoms accordingly.

Potentiates hypokalemic effects of epinephrine.

Potassium-depleting drug that potentiates the hypokalemic effects of epinephrine.

Use with caution when coadministering febuxostat with theophylline. Febuxostat altered the metabolism of theophylline in humans.

Fexinidazole inhibits CYP1A2, increasing theophylline concentrations and risk of adverse reactions.

Potential interaction due to fluvoxamine inhibition of CYP1A2, which is involved in theophylline metabolism.

May decrease phenytoin serum levels; dose adjustment may be required.

Golimumab may normalize CYP450 enzyme formation, potentially affecting theophylline metabolism. Monitoring and dose adjustment recommended.

Monitoring of drug concentration recommended upon initiation or discontinuation of infliximab; individual dose adjustment may be needed.

Monitoring of drug concentration recommended upon initiation or discontinuation of AVSOLA; individual dose adjustment may be needed.

TNF blocker may normalize CYP450 enzyme formation, potentially decreasing theophylline exposure. Monitor drug concentration and adjust dosage upon initiation or discontinuation.

Increased clearance of theophylline when used concomitantly with lansoprazole.

Exposure to theophylline may be reduced when coadministered with leflunomide. Monitor and adjust dose as required.

Exposure of theophylline may be reduced in patients taking leflunomide. Monitor and adjust dose as required.

Small decrease (~16%) in clearance of cetirizine; higher theophylline doses could have greater effect.

Concomitant administration of other fluoroquinolones with theophylline has resulted in prolonged elimination half-life, elevated serum theophylline levels, and increased risk of toxicity.

Other fluoroquinolones have resulted in prolonged theophylline elimination, elevated serum levels, and increased risk of adverse reactions.

COCs containing ethinyl estradiol may inhibit the metabolism of theophylline.

Increased plasma concentrations reported with concomitant administration of oral contraceptives containing ethinyl estradiol.

May reduce the sedative effects of lorazepam.

Theophylline clearance may decrease when hyperthyroid patients become euthyroid; dose reduction may be needed.

Methotrexate increases theophylline plasma concentrations. Monitor theophylline levels and adjust dosage accordingly.

Metreleptin may alter CYP450 metabolism of theophylline. Drug concentration monitoring and dose adjustment recommended upon initiation or discontinuation.

Increased theophylline metabolism reported with smoking of marijuana; effect similar to that following smoking tobacco.

Smoking cessation with nicotine replacement may require dose decrease due to deinduction of hepatic enzymes.

CHCs may inhibit metabolism and increase plasma concentrations of theophylline.

Oral contraceptives may inhibit metabolism of theophylline, increasing its plasma concentrations.

Oral contraceptives may inhibit metabolism of theophylline, increasing its plasma concentrations.

COCs containing ethinyl estradiol may inhibit metabolism of theophylline, potentially increasing its plasma concentrations.

Ethinyl estradiol may inhibit the metabolism of theophylline and increase its plasma concentrations.

Systemic quinolone administration has been shown to elevate plasma concentrations of theophylline.

CYP1A2 substrate with narrow therapeutic index. Use with caution as osilodrostat may affect theophylline metabolism.

Paroxetine increases plasma concentrations of theophylline. Dosage may need decrease with concentration and tolerability monitoring.

PEGASYS inhibits CYP1A2, increasing theophylline AUC by 25%. Monitor serum levels and adjust dose accordingly.

May decrease phenytoin serum levels; monitoring of phenytoin levels recommended.

May decrease phenytoin serum levels; monitoring of phenytoin levels recommended.

Primaquine may inhibit CYP1A2 and increase theophylline exposure; increased monitoring for adverse reactions is recommended.

CYP1A2 substrate/inhibitor that may increase propranolol levels; also coadministration decreases theophylline oral clearance by 30-52%.

Theophylline clearance may decrease when hyperthyroid patients on stable theophylline therapy become euthyroid. A reduced dose of theophylline may be needed.

No change in quinine dosage necessary with concomitant use. Patients should be monitored closely for adverse reactions associated with quinine.

No change in quinine dosage necessary with concomitant use. Patients should be monitored closely for adverse reactions associated with quinine.

Methylxanthine that interferes with the vasodilation activity of regadenoson. Patients should avoid consumption for at least 12 hours before regadenoson administration.

Enhances theophylline clearance, resulting in decreased serum theophylline concentrations. Requires higher theophylline doses to achieve therapeutic levels.

Possible interaction via competitive inhibition of CYP1A2 metabolism; caution advised.

Sarilumab may alter theophylline concentrations through CYP modulation; drug concentration monitoring and dose adjustment recommended upon initiation or discontinuation.

SILTUXIMAB may restore CYP450 activities leading to increased metabolism of theophylline. Therapeutic monitoring and dose adjustment recommended upon initiation or discontinuation.

Stiripentol is an inhibitor and inducer of CYP1A2; consider dose adjustment of theophylline when administered concomitantly with DIACOMIT.

Sucralfate reduces the bioavailability of theophylline. Separate dosing administration is recommended.

Inhibits theophylline metabolism, resulting in increased serum theophylline concentrations. May require dose reduction to avoid toxicity.

Teriflunomide may reduce exposure of theophylline. Monitor patients and adjust dose as required.

Tocilizumab may affect theophylline concentrations; therapeutic drug monitoring and dose adjustment recommended upon initiation or discontinuation.

Tocilizumab may affect theophylline exposure; monitor drug concentration and adjust dose as needed.

Smoking cessation with varenicline may alter theophylline pharmacokinetics or pharmacodynamics, necessitating dose adjustment.

Smoking cessation may alter pharmacokinetics or pharmacodynamics, necessitating dose adjustment.

Rare cases of increased theophylline levels and toxicity reported with zafirlukast addition. Zafirlukast levels decreased approximately 30% in some studies, but no effect on theophylline levels in controlled studies.

Azithromycin had a modest effect on theophylline pharmacokinetics. No dosage adjustment recommended.

Small decrease in clearance of cetirizine at low-dose theophylline; larger doses may have greater effect.

No clinically meaningful interaction identified in testing.

No dose adjustment needed when co-administered with montelukast sodium.

No dose adjustment needed when co-administered with montelukast sodium.

Falsely high readings for theophylline reported in vitro when theophylline and probenecid were added to human plasma using Schack and Waxler technique.

Falsely high readings for theophylline reported in vitro when therapeutic concentrations combined with probenecid using Schack and Waxler technique.

CYP1A2 substrate; coadministration did not alter steady-state pharmacokinetics of either drug.

Tiagabine did not affect the pharmacokinetics of theophylline at steady state.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

CYP450 inducer; effects on butorphanol metabolism unknown; smaller initial dose and longer dosing intervals may be needed.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

30% increase Flurazepam Similar to diazepam.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

80% increase Midazolam Similar to diazepam.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

The effect of progesterone on theophylline clearance is unknown. Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Propranolol Similar to cimetidine and pharmacologic interaction.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

25% increase at allopurinol Amino glutethimide Increases theophylline clearance by induction of microsomal enzyme activity. 25% decrease Carbamazepine Similar to aminoglutethimide. 30% increase Phenobarbital (PB) Similar to aminoglutethimide.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

90% increase Thiabendazole Decreases theophylline clearance.

Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.

60% increase Troleandomycin Similar to erythromycin. 33-100% increase depending on troleandomycin dose.