How are drugs metabolized and excreted from the body?

Most drugs must pass through the liver, which is the primary site for drug metabolism. Once in the liver, enzymes convert prodrugs to active metabolites or convert active drugs to inactive forms. The liver’s primary mechanism for metabolizing drugs is via a specific group of cytochrome P-450 enzymes.

How are most drugs excreted from the body quizlet?

The process of removing a drug of its metabolites from the body occurs primarily in the urine. What are the routes of excretion from the body? Urine, sweat & saliva, tears, bile, breast milk and expired air. … The result is an altered version of the original compound called a metabolite.

What the most common route for excretion of drugs from the body?

Renal excretion is the most common route of drug elimination. However, many drugs are excreted into bile via the liver and some volatile substances (primarily gaseous anesthetics) can be excreted via the lungs.

How drugs are metabolized?

Drugs can be metabolized by oxidation, reduction, hydrolysis, hydration, conjugation, condensation, or isomerization; whatever the process, the goal is to make the drug easier to excrete. The enzymes involved in metabolism are present in many tissues but generally are more concentrated in the liver.

Where are most drugs excreted?

Most drugs, particularly water-soluble drugs and their metabolites, are eliminated largely by the kidneys in urine. Therefore, drug dosing depends largely on kidney function. Some drugs are eliminated by excretion in the bile (a greenish yellow fluid secreted by the liver and stored in the gallbladder).

Why are most drugs metabolised and not excreted?

The majority of metabolic processes that involve drugs occur in the liver, as the enzymes that facilitate the reactions are concentrated there. The purpose of metabolism in the body is usually to change the chemical structure of the substance, to increase the ease with which it can be excreted from the body.

What is it called when a drug is excreted from the body quizlet?

Excretion. -The process of removing a drug or its metabolites from the body. *Occurs primarily in the urine. >>Other routes of excretion from the body include in bile, sweat, saliva, tears, feces, breast milk, and exhaled air. Drug Metabolism.

Where does elimination of drugs from the body occurs primarily?

Most drugs (or metabolites) are excreted by the kidneys. Three process can occur in renal excretion: glomerular filtration, tubular secretion and passive reabsorption. Some drugs are eliminated by the liver in the bile and excreted in feces.

Is the most important organ for excretion of drugs and their metabolites?

Although many sites of metabolism and excretion exist, the chief organ of metabolism is the liver, while the organ primarily tasked with excretion is the kidney. Any significant dysfunction in either organ can result in the accumulation of the drug or its metabolites in toxic concentrations.

Where does first pass metabolism occur?

liver The first-pass effect can occur in the gastrointestinal tract, the liver and lung. Although the liver is the main drug metabolizing organ in the body, the gut wall can play an important role in the first-pass metabolism of certain drugs.

Are the routes of drug administration?

A medication administration route is often classified by the location at which the drug is applied, such as oral or intravenous. The choice of routes in which the medications are applied depends not only on the convenience but also on the drug’s properties and pharmacokinetics.

Which drugs are excreted by the kidneys?

drugs excreted by the kidney

What is excretion in pharmacokinetics?

Excretion. Excretion is the process of removing a drug and its metabolites from the body. This usually happens in the kidneys via urine produced in them. Other possible routes include bile, saliva, sweat, tears and faeces.

What is metabolized in the liver?

The liver plays a central role in all metabolic processes in the body. In fat metabolism the liver cells break down fats and produce energy. They also produce about 800 to 1,000 ml of bile per day. … The liver cells convert ammonia to a much less toxic substance called urea, which is released into the blood.

How do drugs get to the liver?

Medicines taken by mouth are shuttled via a special blood vessel leading from the digestive tract to the liver, where a large amount of the medicine is broken down. Other routes of drug administration bypass the liver, entering the bloodstream directly or via the skin or lungs.

How are drugs excreted through bile?

Biliary excretion involves active secretion of drug molecules or their metabolites from hepatocytes into the bile. The bile then transports the drugs to the gut, where the drugs are excreted. The transport process is similar to those described for renal tubular secretion.

What is drug excretion?

Drug excretion is the removal of drugs from the body, either as a metabolite or unchanged drug. There are many different routes of excretion, including urine, bile, sweat, saliva, tears, milk, and stool. By far, the most important excretory organs are the kidney and liver.

How is excretion different from elimination?

Excretion is a process of removal of xenobiotic out of the body through urine by the renal system. … On the other hand, elimination is a broad process of removal of the drug from the body by both hepatic metabolism as well as renal excretion.

Why are drugs metabolised by the liver?

Enzymes located in the endoplasmic reticulum of liver cells protect the organism against an accumulation of lipid-soluble exogenous and endogenous compounds by converting them to water-soluble metabolites which can be easily excreted by the kidney.

What does renally excreted mean?

Renal excretion is the major route of elimination from the body for most drugs. Drug disposition by the kidneys includes glomerular filtration, active tubular secretion, and tubular reabsorption (Fig. 2.12), such that renal drug clearance is defined by the following equation: Cl R = Cl F + Cl S − FR.

What is metabolism in pharmacokinetics?

Metabolism. Metabolism describes the chemical reactions that change drugs into compounds which are easier to eliminate. The products of these chemical reactions are called metabolites.

What are the most common routes by which medications are eliminated from the body quizlet?

Terms in this set (32)

What is detoxification quizlet?

Definition of detoxification. Detoxification is the way the body heals and repairs itself. It always has an internal cleansing process that takes place continuously and naturally.

Which of the following is the main site of drug elimination quizlet?

The kidneys are the primary organ system responsible for drug elimination. To a lesser extent, the GI tract, the respiratory system, sweat, saliva, tears, and breast milk are also involved. Which of the four phases of pharmacokinetics is concerned with solubility?

Which drugs are excreted in bile?

Biliary excretion of compounds can significantly impact the systemic exposure, pharmacological effect and toxicity of certain drugs. Drugs excreted into bile often undergo some degree of reabsorption along the gastrointestinal tract (e.g., mycophenolic acid4, warfarin5, and digoxin3).

Which drugs are excreted unchanged?

By contrast, polar drugs e.g. gentamicin and digoxin, are unable to do this. Such drugs will therefore be excreted unchanged in the urine because they do not need to undergo biotransformation to increase their water solubility.

What is elimination in the body?

There are six organs in the body that eliminate waste: the lungs, skin, kidneys, liver, colon and lymph. With so much upkeep your body is responsible for, elimination is your body’s way of keeping your body in optimal health and free from harmful bacteria. Without it, your body just wouldn’t function properly.

Which of the following promotes excretion of basic drugs?

Which of the following promotes the excretion of basic drugs? Explanation: Acidification of urine using certain compounds such as NH4CL, methionine or ascorbic acids enhances the excretion of basic drugs.

Which of the following is most useful in determining the rate of elimination of a drug in general?

Understanding the concept of half-life is useful for determining excretion rates as well as steady-state concentrations for any specific drug. Different drugs have different half-lives; however, they all follow this rule: after one half-life has passed, 50% of the initial drug amount is removed from the body.