Thereis a deviation of physical functions of absorption, distribution,metabolism, and excretion (ADME) of substances among the elderlypeople. Normally, there is a specific time that a drug should remainin the body after administration. However, this does not happen amongthe elderly adults when they consume antidepressants such asamitriptyline.For instance, to develop an effective pharmacotherapeutic planfor anysubstance,one requires a clear understanding of its ADME, as well as how toalter a particular population.
Thegastrointestinal (GI) tract changes with age and its affects how thebody absorbs drugs. According to Wooten(2012),the aging process reduces GI blood flow and motility. The olderpeople have low gastric acid hence, reduced drug absorption. Age hasa significant influence on the drug distribution in the body.Scientists argue that as the body age, its fat proportion increaseswhile the muscle mass declines. Therefore, drugs that are moresoluble have high distribution capability among the elderly thanamong the young people. Additionally, the older people have low bodywater, which significantly affects the distribution of water-solubledrugs. Therefore, elderly patients taking amitriptylineshould start with a low dose and observe its effects before makingany change.
Theorgan that is responsible for metabolism is the liver. Generally, theelderly have reduced blood flow, which considerably affects drugmetabolism. This is because their liver receives the drug at a lowerrate. Typically, the drugs are eliminated from the body via renalexcretion. For elderly people, their renal function is minimal.According to research, amitriptylinehalf-life elimination is approximately thirty-one hours among ahealthy elderly patient (Wooten,2012).The study also shows that elderly individuals can take up to one weekto eliminate to it in their plasma. Infact, there are significant effects of amitriptylinepharmacokinetics amongthe elderly.
Wooten,J. M. (2012). Pharmacotherapy considerations in elderly adults. SouthMed J, 105(8),437-445.