The Importance of Drug Dose Adjustment

in Elderly Patients with Special

Considerations for Patients on Diverse

Co-medications and Antidepressants

15

Manju Bhaskar, Istvan G. Telessy, and Harpal S. Buttar

Abstract

The geriatric population is escalating globally, and the need for treating infectious

and non-infectious diseases in elderly patients is also correspondingly increasing

worldwide. In clinical trials and under doctor’s office settings, the drug dosages

are generally computed on mg/kg body wt. basis in young adults and middle-aged

men and women (<40 years). It is well recognized that in comparison with the

younger age counterparts, the geriatric subjects are more susceptible to drug-

mediated adverse reactions due to the reduced activity in cytochrome P450

coenzymes and glucuronidation/sulfation mechanisms. Since the body mass in

elderly patients, especially frail elders, is markedly reduced due to sarcopenia,

progressive loss in body fat, and osteoporosis, hence, drug doses based on mg/kg

body wt. usually cannot be applied in this group of patients as is done in relatively

young adults. Most of the physiological functions, including drug metabolizing

and excretory capacity declines in the elderly, consequently cause significant

alterations in the metabolic disposition as well as changes in the pharmacokinetic

(PK) and pharmacodynamic (PD) parameters of administered drugs in elderly

subjects as opposed to the younger individuals. Innumerable studies have shown

M. Bhaskar

Translational Neuroscience Center, National Institutes of Neurological Disorders and Stroke,

Bethesda, MD, USA

I. G. Telessy

Department of Pharmaceutics, Faculty of Pharmacy, University of Pécs, Pécs, Hungary

MedBioFit Lpc, Gödöllö, Hungary

H. S. Buttar (*)

Department of Pathology and Laboratory Medicine, University of Ottawa, School of Medicine,

Ottawa, ON, Canada

e-mail: hsbuttar@bell.net

# The Author(s), under exclusive license to Springer Nature Singapore Pte

Ltd. 2022

R. C. Sobti, N. S. Dhalla (eds.), Biomedical Translational Research,

https://doi.org/10.1007/978-981-16-9232-1_15

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