Furosemide confirmation

A 54-year-old obese woman with type 2 diabetes had rosiglitazone 4 mg bd added to insulin and metformin. Five months later she reported shortness of breath on exertion, paroxysmal nocturnal dyspnea, and peripheral edema. One month later a chest X-ray confirmed bilateral pulmonary edema. The dose of rosiglitazone was reduced to 4 mg/day and furosemide 20 mg/day was added. Her symptoms improved. 

Kreydiyyeh et al. (2001) provided scientific evidence to confirm the laxative property of parsley, as claimed in folk medicine, and explained its mechanism of action. A perfusion technique was used to measure net fluid absorption from rat colon. The addition of an aqueous extract of parsley seeds to the perfusion buffer, and the omission of sodium, both significantly reduced net water absorption from the colon, as compared with the control. Parsley, added to a sodium-free buffer, did not lead to any further significant change in water absorption as compared with parsley alone suggesting that with parsley, sodium absorption was already inhibited. Since K+ and Cl secretion depends on the activity of the NaKCl2 transporter, the latter was inhibited with furosemide, which increased net water absorption significantly. When parsley and furosemide were... 

Intravenous furosemide reportedly increased steady-state theophyUine concentrations by about 20% (SED-11,428). However, this result has not been confirmed (58). 

Recent data suggest that these differences in bioavailability and variability may have clinical implications. For example, several studies have suggested that torsemide is absorbed reliably and is associated with better outcomes than the more variably absorbed furosemide. And while the costs of torsemide exceed those of furosemide, pharmacoeconomic analyses suggest that the costs of care are similar or less with torsemide. These data require confirmation in controlled, double-blinded clinical trials but provide preliminary evidence that the more reliably absorbed loop dimetics may be superior to fmosemide. 

Saugy, M. Meuwly, R Munafo, A. Rivier, L. Rapid high-performance liquid chromatographic determination with fluorescence detection of furosemide in human body fluids and its confirmation by gas chromatography-mass spectrometry. J.Chromatogr., 1991, 564, 567-578 [serum urine fluorescence detection warfarin (IS) pharmacokinetics gradient LOD 10 ng/mL]... 

An established interaction, although direct evidence seems to be limited to this study. The absorption of furosemide is relatively rapid so that giving it 2 to 3 hours before either the colestyramine or colestipol should be an effective way of overcoming this interaction. This needs confirmation. Note that it is normally recommended that other drugs are given 1 hour before or 4 to 6 hours after colestyramine and 1 hour before or 4 hours after colestipol. 

A 65-year-old man with a history of bilateral ureterohydronephrosis with chronic renal insufficiency, hyperuricemia, and bladder carcinoma reported a 2-month history of prurigi-nous lesions on his trunk and limbs. His medications included long-term allopurinol and calcium, and furosemide (dose not stated), which he had taken for 4 months. The diagnosis was confirmed on skin biopsy. One year after stopping furosemide, his lesions were still present but had become less symptomatic. 

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