Furosemide Theophylline

Acetaminophen Amiodarone Carbamazepine Cardiac glycosides Corticosteroids Dicumarol Disopyramide Doxycycline Estrogens Haloperidol Methadone Metyrapone Mexiletine Oral contraceptives Quinidine Theophylline Valproic acid Cyclosporine Dopamine Furosemide Levodopa Levonorgestrel Mebendazole Nondepolarizing muscle relaxant Phenothiazines Sulfonylureas... 

Tricyclic antidepressants, corticosteroids, coumarin anticoagulants, digitoxin, doxycycline, furosemide, oral contraceptives, quinidine, rifampin, theophylline, vitamin D... 

Figure 6.17 The classification of 42 drugs in the (solubility-dose ratio, apparent permeability) plane of the QBCS. The intersection of the dashed lines drawn at the cutoff points form the region of the borderline drugs. Key 1 acetyl salicylic acid 2 atenolol 3 caffeine 4 carbamazepine 5 chlorpheniramine 6 chlorothiazide 7 cimetidine 8 clonidine 9 corticosterone 10 desipramine 11 dexamethasone 12 diazepam 13 digoxin 14 diltiazem 15 disopyramide 16 furosemide 17 gancidovir 18 glycine 19 grizeofulvin 20 hydrochlorothiazide 21 hydrocortisone 22 ibuprofen 23 indomethacine 24 ketoprofen 25 mannitol 26 metoprolol 27 naproxen 28 panadiplon 29 phenytoin 30 piroxicam 31 propanolol 32 quinidine 33 ranitidine 34 salicylic acid 35 saquinavir 36 scopolamine 37 sulfasalazine 38 sulpiride 39 testosterone 40 theophylline 41 verapamil HC1 42 zidovudine.

Drugs that meet one or more of the criteria given above and have been shown to exhibit significant differences in the bioavailability of marketed dosage forms include digoxin, quinidine, furosemide, nitrofurantoin, prednisone, chloramphenicol, theophylline, chlorpromazine, phenytoin, amitriptyline, and phenylbutazone. 

Furosemide increases steady-state theophylline concentrations (SED-11, 428) (SED-14, 673). 

A randomized, controlled study has shown an enhanced diuretic response to furosemide in infants taking theophylline during extracorporeal membrane oxygenation (49). The underlying mechanism was uncertain, but may have been an increase in glomerular filtration rate. 

Ten preterm infants receiving regular theophylline for apnea of prematurity, who subsequently received vancomycin and furosemide, have been studied (52). When vancomycin was introduced in the infants who were established on furosemide and theophylline, there was a consistent failure to achieve therapeutic concentrations. Starting furosemide in infants who were already receiving vancomycin resulted in falls in serum vancomycin to subtherapeutic concentrations in all but one case. Serum concentrations fell by a mean of 24% (range 12-43%), in the 24 hours after the start of furosemide treatment. Two of the 10 infants had persistence... 

Lochan SR, Adeniyi-Jones S, Assadi FK, Frey BM, Marcus S, Baumgart S. Coadministration of theophylline enhances diuretic response to furosemide in infants during extracorporeal membrane oxygenation a randomized controlled pilot study. J Pediatr 1998 133(l) 86-9. 

A 73-year-old man took an unknown number of theophylline modified-release tablets and furosemide 40 mg tablets. He developed a tachydysrhythmia, vomiting, and restlessness. His maximum theophylline concentration was 67 pg/ml and he had hypokalemia (2.8 mmol/1) and hyponatremia (123 mmol/1). The maximum creatine kinase activity was (32 mol/1 [sic]) and the serum myoglobin concentration was 3789 pg/l. He was treated with oral activated charcoal, continuous venovenous hemodialysis, intravenous potassium and sodium chloride, forced diuresis, and continuous intravenous meto-prolol, and survived without sequelae. 

Recommendations have been presented for correction of theophylline doses dnring concomitant medication with some of the above dmgs (SEDA-8, 130) (45). Concomitant therapy with aUopnrinol, cimetidine, erythromycin, furosemide, isoprenahne, or propranolol requires a reduction in dose of abont 20-30% for oleandomycin the reduction shonld be abont 50%. 

Janicke UA, Krudewagen B, Schulz A, Gundert-Remy U. Absence of a chnically significant interaction between theophylline and furosemide. Eur J Chn Pharmacol 198733(5) 487-9I. 

Furosemide (40-80 mg) has been reported to enhance and prolong D-tubocurarine-induced block in anephric patients (63). In animals low doses potentiated D-tubocur-arine (and suxamethonium) probably via presynaptic effects, while high doses (1-40 mg/kg in cats) reversed the neuromuscular actions of these relaxants (64). The effects of high doses were similar to those of theophylline. 

DMSO X 5 X Sulfasalazine, furosemide, atenolol, acetaminophen, propranolol, theophylline, diclofenac, metoprolol, antipyrine, naproxen Watanabe etak, 2004... 

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