What are the main causes of individual variations of drug effects?

What are the main causes of individual variations of drug effects?

Variation in the response to equivalent drug concentrations arises because of various factors, such as differences in receptor number and structure, receptor-coupling mechanisms and physiological changes in target organs resulting from differences in genetics, age and health.

What are the basis for individual responses to drugs?

Drug response can be impacted by several factors including diet, comorbidities, age, weight, drug–drug interactions, and genetics. Individual genetic variation in key genes involved in the metabolism, transport, or drug target can contribute to risk of adverse events108 or treatment failure.

What is biological variation in pharmacology?

Biologic variation (variation in magnitude of response among test subjects in the same population given the same dose of drug) also occurs.

What is the pharmacological response?

Pharmacological responses are based on the binding of the drug with its corresponding target. The drug concentration at the receptor site controls its effect—factors such as aging, disorders, or other drugs influence the drug PD.

What is individual variation?

In our view ‘individual variation’ refers to those differences among individuals that are either permanent or change slowly (e.g. body size, fat reserves) in relation to the dynamics of group movement.

How does body size affect drug response?

“In patients with extra body weight, the drugs may not get to those optimal levels, as there is more body mass for the drug to saturate,” he explains. Other changes that result from obesity can also affect how quickly drugs are broken down or eliminated from the body.

What is individual drug variation?

Variations in response to drugs may be pharmacodynamic, implying inter-individual differences in the response of receptors in equal concentrations of drug, or pharmacokinetic, implying that individuals receiving the same dose of drug will have different concentrations of drug in their body fluids.

How does genetics affect drug response?

Because of their genetic makeup, some people process (metabolize) drugs slowly. As a result, a drug may accumulate in the body, causing toxicity. Other people metabolize drugs so quickly that after they take a usual dose, drug levels in the blood never become high enough for the drug to be effective.

How do you calculate biological variation?

For example, for potassium, the analytical imprecision in ITU (taken from the QC) is CV = 2.1 %. The biological variation (taken from the Internet database) is 4.8 %. Thus, RCV for P < 0.05 is 21/2 × 1.96 × (2.12 + 4.82)1/2 = 14.5 % – so only changes in potassium greater than 14.5 % are significant.

How a genetic variation will affect drug response?