Dehydration, diuretic-induced

Aimstrong, L.E., Costill, D.L., Fink, W.J. (1985). Influence of diuretic-induced dehydration on competitive running performance. Med. Sci. Sports Exerc. 17,456-461. 

Fluid and sodium balance are important to the safe use of lithium. Both dehydration and a negative sodium balance (for example a low salt intake, diuretic-induced sodium loss) will reduce renal lithium clearance and predispose to toxicity (331). Hyponatremia (for example, secondary to polydipsia or SIADH) may also increase the risk of lithium toxicity (332). 

Because Henle s loop is indirectly responsible for water reabsorption by the downstream collecting duct, loop diuretics can cause severe dehydration. Hyponatremia is less common than with the thiazides (see below), but patients who increase water intake in response to hypovolemia-induced thirst can become severely hyponatremic with loop agents. Loop agents are sometimes used for their calciuric effect, but hypercalcemia can occur in volume-depleted patients who have another—previously occult—cause for... 

T Effects W/ antihypertensives, cliazoxicle, nitrates, EtOH T effects OF ACEIs, Li T risk of hypokalemia W/ amphotericin B, corticosteroids, mezlocillin, piperacillin, ticarcillin effects W/ cholestyramine, colestipol, NSAIDs EMS Monitor ECG for hypokalemia (flattened T waves) T risk of photosensitivity Rxns use caution w/ other diuretics, may T risk of electrolyte imbalances and dehydration may affect glucose (hyperglycemia) OD May cause dehydration, hypotension, drowsiness, headache, and fatigue symptomatic and supportive, do not do anything that would force greater fluid loss (ie, induce V)... 

Drugs that can disturb fluid-electrolyte balance must be used with caution in patients with certain types of liver impairment. Diuretics, for example, are often required to treat ascites but can cause hypo-natraemia, hypo- or hyperkalaemia. A disturbance in electrolyte balance can lead to encephalopathy in susceptible patients such as cirrhotics or those with acute liver failure. Dehydration induced by diuretics is a common precipitant of hepatic encephalopathy. The mechanism is not fully understood, but could possibly be due to the reduced metabolism of hepatic toxins because of hepatic hypoxia [5]. 

Like other diuretics, thiazides can induce hypokalemia, hyponatremia, hypochloiemia. hypomagnesemia. hypercalcemia, hyperuricemia, glucose intolerance, dehydration, and changes in the lipid profile. Thiazides may also cause photosensitivity reactions. 

B. Chronic intoxication may occur in patients on stable therapeutic doses. Lithium is excreted by the kidney, where it is handled like sodium any state that causes dehydration, sodium depletion, or excessive sodium reabsorption may lead to increased lithium reabsorption, accumulation, and possibly intoxication. Common states causing lithium retention include acute gastroenteritis, diuretic use, use of nonsteroidal anti-inflammatory drugs or angiotensinconverting enzyme (ACE) inhibitors, and lithium-induced nephrogenic diabetes insipidus. 

Urinary tract Contrast-induced nephrotoxicity has been reviewed in successive volumes of SEDA [SEDA-29, 575 SEDA-30, 535 SEDA-31, 731 SEDA-32, 846]. The EIDOS and DoTS descriptions of this reaction are shown in Figure 2. Susceptibility factors include age (over 70 years), drugs (nephrotoxic drugs, such as non-steroidal anti-inflammatory drugs metformin mannitol, and diuretics, particularly loop diuretics multiple repeat exposures to contrast media within 72 hours), and diseases (pre-existing renal insufflciency, particularly if it is associated with diabetes melli-tus, congestive heart failure, dehydration). There is also an increased risk in organ transplant recipients. 

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