Loop diuretics adverse effects

Cephalexin (Keflex, Panixine DisperDose) [Antibiotic/ Cephalosporin-1st Generation] Uses Skin, bone, upper/lower resp tract, urinary tract Infxns Action lst-gen cephalosporin X- cell wall synth Dose Adults. 250-1000 mg PO qid Feds. 25—100 mg/kg/d PO - qid 4- in renal impair (on empty stomach) Caution [B, +] Contra Cephalosporin allergy Disp Caps, tabs, susp SE D, rash, eosinophilia, T LFTs Interactions T Nephrotox W/aminoglycosides, loop diuretics T effects W/probenecid EMS T Risk of adverse effects w/ loop diuretics monitor for signs of electrolyte disturbances and hypovolemia d/t D monitor pt for super Infxn OD May cause N/V/D, Szs, muscles spasms symptomatic and supportive... 

Several adaptive mechanisms by the kidney limit effectiveness of loop diuretic therapy. Postdiuretic sodium retention occurs as the concentration of diuretic in the loop of Henle decreases. This effect can be minimized by decreasing the dosage interval (i.e., dosing more frequently) or by administering a continuous infusion. Continuous infusion loop diuretics may be easier to titrate than bolus dosing, requires less nursing administration time, and may lead to fewer adverse reactions. 

Equipotent doses of loop diuretics (furosemide, bumetanide, torsemide, ethacrynic acid) have similar efficacy. Ethacrynic acid is reserved for sulfa-allergic patients. Continuous infusions of loop diuretics appear to be more effective and to have fewer adverse effects than intermittent boluses. An initial IV loading dose (equivalent to furosemide 40 to 80 mg) should be administered before starting a continuous infusion (equivalent to furosemide 10 to 20 mg/hour). 

Offers potential advantages over other loop diuretics, including a longer duration of action and fewer adverse electrolyte and metabolic effects available data not extensive or convincing enough at present to recommend replacement of standard loop diuretic (furosemide) considered alternative in refractory patients... 

All loop diuretics, with the exception of ethacrynic acid, are sulfonamides. Therefore, skin rash, eosinophilia, and less often, interstitial nephritis are occasional adverse effects of these drugs. This toxicity usually resolves rapidly after drug withdrawal. Allergic reactions are much less common with ethacrynic acid. 

Summary of adverse effects commonly observed with loop diuretics. 

Q10 Do loop diuretics produce any adverse effects in the patient ... 

Q8 In addition to the intended therapeutic effects, thiazide diuretics can have adverse effects of hypokalaemia, hyperglycaemia and hyperuricaemia. These are not often observed when the usual low dose of thiazide is used. If the dosage is increased, the therapeutic effect is not greatly enhanced, but the likelihood of adverse effects increases considerably. It is therefore better to change to a more powerful agent, such as a loop diuretic, than to increase the dose of the thiazide. 

The loop diuretics increase the renal excretion of lithium after single-dose intravenous administration in both animals (711) and man (712). Furosemide has been used to treat lithium intoxication (713). The effect of etacrynic acid is larger than those of furosemide and bumetanide (712). However, long-term treatment with furosemide and bumetanide can cause lithium intoxication in some patients (714,715), perhaps by causing sodium depletion and a secondary increase in lithium reabsorption. An adverse interaction of lithium during long-term therapy with etacrynic acid is therefore theoretically likely. 

Etaciynic acid (ethacrynic acid) is a loop diuretic with similar actions to furosemide and bumetanide. However, it has more adverse effects than the other loop diuretics and offers no clear advantages. 

Furosemide (frusemide) Loop diuretic inhibits the Na, K, 2Cr-cotransporter in the thick ascending limb of the loop of Henle Initially administered as an i.v, bolus Fast acting (response within 1 h after administration) Increases urine excretion of Na and water Few adverse effects Inexpensive May not reach active site unless high doses are used High doses can precipitate transient vasoconstriction... 

Although furosemide (fmsemide) is administered commonly in oliguric ARF, there is controversy over whether this drug decreases the incidence of ARF in high-risk human patients or enhances recovery (Dishart Kellum 2000). In fact, there have been few studies that have addressed this question in a prospective, blinded fashion in comparison to placebo treatment. In a recent report that compared furosemide (fmsemide, 3mg/kg i.v. four times a day for 21 days) or torasemide (another loop diuretic) with placebo treatment in 92 humans patients with ARF, the administration of a loop diuretic had a positive effect on urine output during the initial 24 h of treatment but did not shorten the dialysis times or improve the patient outcome (Shilliday et al 1997). Nevertheless, because the adverse effects associated with furosemide (fmsemide) use are few, it remains a common treatment in oliguric ARF. 

Loop diuretics (e.g., ethacrynic acid and furosemide) inhibit the NaVK /M cotransporter on the luminal membrane of the thick ascending loop. The mechanisms causing their diuretic actions (Figure 111-6-3) and their clinical uses and adverse effects are discussed. 

He asks you about any potential adverse effects. What should you tell him He tells you that he has been taking a loop diuretic for his mild hypertension and wonders if this drug might have any effect on his use of warfarin. What should you tell him Mr Jones also wants to know whether he should modify his diet in any way because of the warfarin. What advice can you give him on diet (and drink) ... 

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