Renal function elderly patients

Elderly Geriatric patients often require reduced dosage because of impaired renal function. In patients with severe impairment, dosage should not exceed 20 g in 48 hours. Monitor serum magnesium in such patients. 

Renal/Hepatic function impairment Use with caution and in reduced doses in patients with hepatic impairment metabolism may be impaired, leading to drug accumulation. Use with caution in patients with significantly impaired renal function. Elderly Be cautious in dose selection for an elderly patient, usually starting at the low end of the dosing range. Elderly patients may be sensitive to the anticholinergic side effects of TCAs. 

Norfloxacin - Absorption is rapid. Food or dairy products may decrease absorption. Steady-state norfloxacin levels will be attained within 2 days of dosing. Norfloxacin is eliminated through metabolism, biliary excretion, and renal excretion. Renal excretion occurs by glomerular filtration and tubular secretion. In healthy elderly volunteers, norfloxacin is eliminated more slowly because of decreased renal function. In patients with Ccr rates 30 mL/min/1.73 m or less, the renal elimination decreases so that the effective serum half-life is 6.5 hours dosage alteration is necessary. 

There have been several reports of impaired renal function in patients taking ketorolac (SEDA-17, 112) (SEDA-18, 105) (SEDA-22, 117). The severity varies from slight to severe forms of renal insufficiency, which may even occur after a single dose of 30 mg. Because recent major surgery is considered a risk factor for renal insufficiency, particularly in elderly patients, the use of ketorolac, or other NSAIDs, for postoperative pain management is warranted only in carefully selected patients. Furthermore, a case report confirmed that oral ketorolac can cause acute renal insufficiency in young subjects without any predisposing factors (SEDA-21,106). 

The more basic interactions between piperacillin and methotrexate and its major metabolite 7-hydroxymetho-trexate have been stndied in rabbits (255). The interaction was mainly cansed by rednced renal clearance of both methotrexate and its metabolite. The anthors concluded that renal function in patients taking this combination should be monitored, with adequate fluid intake, especially in elderly patients, because dehydration may accelerate the occurrence of toxicity. 

NSAIDs can cause renal impairment, particularly in patients in whom prostaglandins are playing an important role in maintaining renal function. Such patients include those taking diuretics, the elderly and those with concurrent conditions such as congestive heart failure and ascites. Hence the combination of diuretics and NSAIDs may increase the nephrotoxicity ofNSAIDs.30. - ... 

The older adult is more susceptible to the nephrotoxic effects of the cephalosporins particularly if renal function is already diminished because of age or disease. If renal impairment is present, a lower dosage and monitoring of blood creatinine levels are indicated. Bood creatinine levels greater than 4 mg/dL indicate serious renal impairment. In elderly patients with decreased renal function, a dosage adjustment may be necessary. 

The antipsychotic dru are used cautiously in patients exposed to extreme heat or phosphorous insecticides and in those with respiratory disorders, glaucoma, prostatic hypertrophy, epilepsy, decreased renal function, lactation, or peptic ulcer. The antipsychotic drags are used cautiously in elderly and debilitated patients because these patients are more sensitive to the antipsychotic dragp. lithium is used cautiously in patients who are in situations in which they may sweat profusely and those who are suicidal, have diarrhea, or who have an infection or fever. 

Another key feature of the thiazide-type diuretics is their limited efficacy in patients whose estimated renal function is reduced, such as the elderly. For example, patients with estimates of reduced renal function, such as those with a glomerular filtration rate (GFR) below 30 mL/minute, should be considered for more potent loop type diuretics such as furosemide. Clinicians often fail to either reconsider the role of thiazide diuretics prescribed to individuals whose renal function has been declining or fail to recognize the likely prevalence of renal compromise in the elderly to begin with. 

NSAIDs can cause renal insufficiency when administered to patients whose renal function depends on prostaglandins. Patients with chronic renal insufficiency or left ventricular dysfunction, the elderly, and those receiving diuretics or drugs that interfere with the renin-angiotensin system are particularly susceptible. Decreased glomerular filtration also may cause hyperkalemia. NSAIDs rarely cause tubulointerstitial nephropathy and renal papillary necrosis. 

The recommended starting doses (see Table 19-5) should be reduced in elderly patients who may have compromised renal or hepatic function. Dosage can be titrated every 1 to 2 weeks (longer interval with chlorpropamide) to achieve glycemic goals. 

Varenicline FDA approved in 2006 Titrate up to 1 mg orally twice daily 3-6 months Monitor renal function, especially in elderly patients. Nausea, headache insomnia are dosedependent adverse effects. Al... 

In addition to treating insomnia, gabapentin has been used to treat epilepsy, anxiety disorders, and bipolar disorder. It is generally well tolerated with sedation and headaches being the only prominent side effects. Because gabapentin is excreted unchanged in urine, it does not require metabolism by the liver. It is therefore easily eliminated by elderly patients and those with liver disease, although it should be used with caution in those with poor renal (kidney) function. 

Correlation between the daily dose of digoxin and plasma digoxin levels in randomly selected patients (E8) is poor, but it is improved if only those with normal renal function are considered (C4, R4). The difference is consistent with the primary role played by the kidneys in the excretion of digoxin and the likelihood that many patients treated with digoxin are elderly and infirm and have impaired renal function (B6). 

B6. Baylis, E. M., Hall, M. S., Lewis, G., and Marks, V., Effects of renal function on plasma digoxin levels in elderly ambulant patients in domiciliary practice. Brit. Med. J. 1, 338-341 (1972). 

Elderly In general, use caution in dose selection for an elderly patient, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy. 

Because elderly patients are more likely to have decreased renal function, it may be useful to monitor renal function. 

Special patient populations Initial and maintenance dosing should be conservative in patients with advanced age because of the potential for decreased renal function. Base any dosage adjustment on a careful assessment of renal function. Generally, do not titrate elderly, debilitated, or malnourished patients to the maximum dose. Do not initiate metformin IR and ER treatment in patients 80 years of age and older unless measurement of Ccr demonstrates that renal function is not reduced. 

Eideriy Because aging is associated with reduced renal function, use metformin with caution as age increases. Generally, do not titrate elderly patients to the maximum dose of metformin (see Administration and Dosage). 

Eideriy Elderly patients may have higher blood levels and AUC of lisinopril, ramiprilat, quinaprilat, and moexiprilat. This may relate to decreased renal function rather than to age itself. 

Elderly Fenofibric acid is known to be substantially excreted by the kidney, and the risk of adverse reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, take care in dose selection. 

Elderly (77 years of age and older) - 5 mg once daily as recommended. Renal/Hepatic function impairment - In patients 12 years of age and older with decreased renal function (Ccr 11 to 31 mL/min), hemodialysis patients (Ccr less than 7 mL/min), and in hepatically impaired patients, 5 mg once daily is recommended. 

Starting dose 75 mg 3 times/day or 50 mg 4 times/day. Reduce initial dose to % to 1/3 in elderly or debilitated patients or those with impaired renal function. 

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