**Abstract**

The elderly, above the age of 65, are heterogeneous population with increased morbidity. They are more exposed to medication due to multiple health problems. The natural physiological changes and alterations in homeostatic regulation alter drug response and increase the risk of adverse drug reactions in them. Multi-prescription, polytherapy also increases the incidence of adverse reactions. It is difficult to diagnose adverse reactions in the elderly as they often present with nonspecific symptoms and to differentiate whether they are due to medications or not. Most of the hospital admissions due to adverse reactions are predictable and 50% among them are preventable Type A reactions as most of the errors occur during prescribing or monitoring of drugs. Prescribers should review the medication list regularly and be cautious in prescribing new medicines. Physicians' awareness of the physiology and pharmacology of aging can reduce adverse reactions that help in promoting better health care for older adults.

**Keywords:** elderly, adverse reactions, polytherapy
