What are the pharmacodynamic changes in the elderly?

The most important pharmacodynamic differences with age for cardiovascular agents are the decrease in effect for beta-adrenergic agents. This decline in response in vascular, cardiac, and pulmonary tissue may be due to a decrease in Gs protein interactions.

How does Ageing affect pharmacokinetics?

As ageing is associated with some reduction in first-pass metabolism, bioavailability of a few drugs can be increased. With ageing body fat increases and total body water as well as lean body mass decrease.

How does age affect pharmacokinetics and pharmacodynamics?

In people who are aged >65 years, pharmacokinetics are influenced more by the loss of kidney function than by the aging process of any other organ. Drug dosing must be adjusted to both changing pharmacokinetics and pharmacodynamics; the pharmacodynamics might be influenced by the aging of other organs, too.

What are the different physiological changes of elderly?

Physiological changes occur with aging in all organ systems. The cardiac output decreases, blood pressure increases and arteriosclerosis develops. The lungs show impaired gas exchange, a decrease in vital capacity and slower expiratory flow rates.

How does pharmacokinetics affect aging in older adults?

Pharmacokinetics in Older Adults. With aging, there are changes in all these areas; some changes are more clinically relevant. The metabolism and excretion of many drugs decrease, requiring that doses of some drugs be decreased. Toxicity may develop slowly because concentrations of chronically used drugs increase for 5 to 6 half-lives,

How does aging affect the metabolism of drugs?

As the hepatic first-pass effect o … Aging involves progressive impairments in the functional reserve of multiple organs, which might also affect drug metabolism and pharmacokinetics. In addition, the elderly population will develop multiple diseases and, consequently, often has to take several drugs.

How does the elderly affect the absorption of drugs?

Drug absorption changes in the elderly Gastrointestinal system (rarely clinically significant) • acid production generally unchanged • drug-drug interaction may alter absorption • splanchnic blood flow decreases (with little effect on drug absorption) (Table 23.2) Pharmacokinetics: distribution

How does change in pharmacokinetics affect the body?

Any change, like crushing tablets , that may affect the rate of absorption, metabolism or excretion of a drug may also effect whether that drug reaches toxic levels or drops to sub-therapeutic levels.