Parte di kinetics

The ability of a molecule to dissolve in water or an aqueous solution.

The ability of a molecule to dissolve in fats or lipids.

The movement of molecules through the gaps between cells.

The movement of molecules across a membrane that requires energy.

The movement of molecules across a membrane without requiring energy.

The form of a molecule that can easily pass through the cell membrane.

The study of foreign substances in the body, including drugs.

The process by which a drug is absorbed into the bloodstream and distributed throughout the body.

The fraction of a drug that is not bound to plasma proteins.

Drugs that bind to plasma proteins are transported throughout the body, similar to how natural molecules use this mechanism.

The time it takes for the concentration of a drug in the body to decrease by half.

A drug's affinity for binding to plasma proteins; a high binding percentage means the drug spends more time in the bloodstream.

A combination of Trimethoprim and Sulfonamides enhances their antimicrobial effects against bacteria.

Warfarin, a common anticoagulant, inhibits platelet aggregation, preventing blood clotting.

A cephalosporin antibiotic known for its long half-life and high binding to plasma proteins.

Examples of drugs with low plasma protein binding, like paraquat (herbicide) and digoxin (cardiac drug).

The process by which the body breaks down and changes the chemical structure of substances, often to make them easier to eliminate.

The ability of a substance to dissolve in fats or oils.

The ability of a substance to dissolve in water.

The process of converting a lipophilic substance into a more hydrophilic substance, making it easier to eliminate from the body.

Elimination of substances from the body through urine or bile.

The ability of a substance to produce a desired effect in the body.

The state of a substance losing its effectiveness in the body.

The movement of a drug from the bloodstream to the target tissue.

The process of a drug moving from highly perfused organs (like the brain) to less perfused organs (like muscle) and then back to the bloodstream. This can happen due to concentration differences.

Drugs that easily pass through cell membranes and reach highly perfused organs like the brain.

Organs that receive a large amount of blood flow.

Organs that receive a relatively lower amount of blood flow.

A type of anesthetic that affects the brain and can have prolonged effects due to redistribution.

Specific formulations of drugs designed to release slowly and prolong their effect, often used in animals.

The process of a drug being broken down and eliminated by the body.

The blood-brain barrier (BBB) is a protective layer that controls the movement of substances from the bloodstream into the brain. It prevents harmful substances from entering the brain, but also restricts the entry of some essential medications.

In some individuals, the BBB may be less effective, allowing drugs to pass through more easily. This can lead to neurological side effects because the drugs can directly affect the brain.

In newborn babies, the BBB is more permeable, making them more vulnerable to certain toxins like methyl mercury. This can lead to serious neurological disorders.

Inflammation, such as meningitis, can affect the BBB, making it less effective at protecting the brain. This allows drugs that normally wouldn't enter the brain to pass through.

The distribution of a drug throughout the body is influenced by its affinity for plasma proteins and the blood flow to different organs. Drugs are distributed faster in organs with high blood flow.

Organs with high perfusion rates, like the central nervous system (CNS), kidneys, heart, and lungs, receive drugs quickly. Muscles and skin receive drugs slower, and tissues like teeth, ligaments, and tendons receive the lowest amount of drug.

The perfusion rate is a limiting factor not only for drug distribution but also for re-distribution, which is the movement of a drug from one part of the body to another.

Drugs can be distributed quickly in organs with high perfusion rates, while tissues with slower blood flow receive a lower concentration of the drug. This difference in distribution can affect the drug's efficacy and side effects.

Aflatoxin B1 is a substance produced by the fungus Aspergillus flavus. This toxin can be ingested by humans and animals through contaminated food and feed.

The liver tries to detoxify aflatoxin B1 by converting it into an epoxide. However, this process actually makes the toxin even more harmful because epoxides are highly reactive and can damage DNA.

Aflatoxin B1 epoxide can bind to guanine bases in DNA, altering the DNA structure and causing cancer.

Benzopyrene, a compound found in tobacco smoke, is also metabolized into a reactive epoxide. This epoxide can damage DNA, leading to lung cancer.

Not all biotransformations detoxify substances. Sometimes, they can create reactive metabolites that can damage the body.

Ciprofloxacin, an antibiotic drug, undergoes biotransformation to form a metabolite called M1. This process doesn't convert the drug into a non-lipophilic form, showing that not every transformation follows a specific pattern.

Toxicity caused by a substance can vary depending on the organism. Aflatoxin B1, for example, can cause various toxic effects in animals, such as teratogenicity (birth defects) and mutagenicity.

Aflatoxin B1 is routinely monitored and controlled in food safety programs to prevent its harmful effects on both humans and animals.