Pharmacokinetics elderly

Elderly Pharmacokinetics in the elderly are similar to those seen in younger adults. Pregnancy Category C. 

Elderly- Pharmacokinetic studies demonstrated a reduced clearance of... 

Elderly Pharmacokinetic profile in elderly patients is not established. Because elderly individuals frequently have a reduced glomerular filtration rate, pay particular attention to assessing renal function before and during ganciclovir therapy. 

Cusack B, Kelly J, O Malley K, et al. Digozin in the elderly pharmacokinetic consequences of old age. Clin Pharmacol Ther 1979 25 772-776. 

Greenblatt DJ, Shader Rl. Benzodiazepines in the elderly pharmacokinetics and drug sensitivity. In Saizman C, Lebowitz BD, eds. Anxiety in the eideriy. Treatment and research. New York Springer, 1991. 

Aniracetam (6), launched in 1993 in both Japan and Italy for the treatment of cognition disorders, is in Phase II trials in the United States as of this writing. In clinical studies it has been shown to cause some improvement in elderly patients with mild to moderate mental deterioration (63), and in geriatric patients with cerebral insufficiency (64). In a multicenter double-blind placebo-controUed trial involving 109 patients with probable AD, positive effects were observed in 36% of patients after six months of treatment (65), a result repeated in a separate study of 115 patients (66). A review of the biological and pharmacokinetic properties, and clinical results of aniracetam treatment in cognitively impaired individuals is available (49). 

Geriatric factors a variety of factors, both pharmacokinetic and pharmacodynamic, that contribute to variable dmg responses in the elderly. These responses are not seen for every class of dmg. Thus, the depressant effects of the glycosides also appear to increase with aging (116,117). 

Vigilance for drug-drug interactions is required because of the greater number of medications prescribed to elderly patients and enhanced sensitivity to adverse effects. Pharmacokinetic interactions include metabolic enzyme induction or inhibition and protein binding displacement interactions (e.g., divalproex and warfarin). Pharmacodynamic interactions include additive sedation and cognitive toxicity, which increases risk of falls and other impairments. 

M Mayersohn. Special pharmacokinetic considerations in the elderly. In WE Evans, JJ Schentag, WJ Jusko, eds. Applied Pharmacokinetics Principles of Therapeutic Drug Monitoring. 3rd ed. Vancouver, WA Applied Therapeutics, 1992, pp. 9-1-9-43. 

M Mayersohn. Pharmacokinetics in the elderly. Environ Health Perspect 102 (suppl 11) 119 124, 1994. 

M Mayersohn, The xylose test to assess gastrointestinal absorption in the elderly a pharmacokinetic evaluation of the literature. J Gerontol 37 300-305, 1982. 

Within the medical community it has been acknowledged that elderly patients often respond to drug therapy differently from their younger counterparts. Aside from alteration of various pharmacokinetic and pharmacodynamic processes, elderly patients tend to suffer from a number of chronic conditions and, thus, have more complex dosage regimens. Additionally, a variety of physical limitations prevalent among the elderly may hinder their ability to self-administer medication. 

Before the start of any formal laboratory work, the characteristics of the drug and excipients to be used must be considered. When performing this evaluation, it is necessary to keep in mind all of the pharmacokinetic and physical changes experienced by the elderly and pediatric population. 

Some indications for plasma level monitoring include inadequate response, relapse, serious or persistent adverse effects, use of higher than standard doses, suspected toxicity, elderly patients, children and adolescents, pregnant patients, patients of African or Asian descent (because of slower metabolism), cardiac disease, suspected noncompliance, suspected pharmacokinetic drug interactions, and changing brands. 

From Cusack BJ. Pharmacokinetics in older persons. Am J Geriatr Pharm 2004 2 274-302 and Chapron DJ. Drug disposition and response. In Delafuente JQ Stewart RB, eds. Therapeutics in the Elderly 3rd ed. Cincinnati, OH Harvey Whitney, 2000 257-288. 

The pharmacokinetics of tegaserod in patients with IBS are comparable to those in healthy individuals, and similar between men and women. No dosage adjustment is required in elderly patients or those with mild-to-moderate hepatic or renal impairment [46,47]. 

Tumheim K (2003) When drug therapy gets old pharmacokinetics and pharmacodynamics in the elderly. Exp Gerontol 38(8) 843-853... 

Sonne J, Loft S, Dossing M et al. (1991) Single dose pharmacokinetics and pharmacodynamics of oral oxazepam in very elderly institutionalised subjects. Br J Chn Pharmacol 31(6) 719-722 Taylor S, McCracken CF, Wilson KC et al. (1998) Extent and appropriateness of benzodiazepine use. Results from an elderly urban community. Br J Psychiatry 173 433—438... 

There are many prevalent conditions in the elderly that can interfere with the normal pharmacokinetic process. The changes in the gastrointestinal tract due to aging do not normally give any problems with drug treatment but in combination with diverse chronic ailments, they do. The absorption of drugs can be disturbed by the... 

The physiological changes and other aspects in the elderly makes this even more complicated. Example of this is decreased stomach acidity decreased motility decreased blood-flow to liver and gastrointestinal tract changed pharmacokinetics and -dynamics polypharmacy swallowing problems bad nutritional status and lack of documentation. 

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