What is the difference between water soluble and fat soluble drugs?

What is the difference between water soluble and fat soluble drugs?

Drugs that dissolve in water (water-soluble drugs), such as the antihypertensive drug atenolol, tend to stay within the blood and the fluid that surrounds cells (interstitial space). Drugs that dissolve in fat (fat-soluble drugs), such as the antianxiety drug clorazepate, tend to concentrate in fatty tissues.

Why are lipid soluble drugs more easily absorbed in general than water soluble drugs?

In general, lipid-soluble drugs, and drugs composed of smaller molecules, cross the cell membrane more easily and are more likely to be absorbed by passive diffusion.

Why are lipid soluble drugs better?

Absorption. Both the lipid solubility of the drug and the pH of the gastric tissues affect drug absorption from the GI tract. Lipid-soluble drugs are absorbed more rapidly than non–lipid-soluble drugs.

How does solubility affect drug absorption?

Drug absorption depends on the lipid solubility of the drug, its formulation and the route of administration. A drug needs to be lipid soluble to penetrate membranes unless there is an active transport system or it is so small that it can pass through the aqueous channels in the membrane.

Are lipid soluble drugs absorbed faster?

Because the cell membrane is lipoid, lipid-soluble drugs diffuse most rapidly. Small molecules tend to penetrate membranes more rapidly than larger ones. Most drugs are weak organic acids or bases, existing in un-ionized and ionized forms in an aqueous environment.

Is alcohol water or lipid soluble?

Alcohol is a very small molecule and is soluble in “lipid” and water solutions. Because of these properties, alcohol gets into the bloodstream very easily and also crosses the blood brain barrier.

What makes a drug lipid soluble?

A substance will become more lipid soluble in a solution with a pH similar to its own pH. A weak base is more lipid-soluble in an alkaline solution. A weak base is more WATER-soluble in an acidic solution.

Do lipid soluble drugs cross the blood brain barrier?

General Properties of the BBB Low lipid (fat) soluble molecules do not penetrate into the brain. However, lipid soluble molecules, such as barbituate drugs, rapidly cross through into the brain. Molecules that have a high electrical charge are slowed.

How are fat soluble drugs different from water soluble drugs?

For example, the antibiotic rifampin, a highly fat-soluble drug, rapidly enters the brain, but the antibiotic penicillin, a water-soluble drug, does not. In general, fat-soluble drugs can cross cell membranes more quickly than water-soluble drugs can.

Where are fat soluble and water soluble vitamins found?

Any excess of water-soluble vitamins, like the Vitamin B complex or Vitamin C, are excreted through the urination process. Many B vitamins and Vitamin C can be found in vegetables (like leafy greens and other green vegetables) and fruits (like citrus fruits). Fat-soluble vitamins dissolve in—you guessed it—fat.

Why do fat soluble substances diffuse faster through cell membranes?

Fat-soluble substances diffuse faster through cell membranes because of their ability to interact with the hydrophobic tail. Water-soluble (hydrophilic) substances don’t have this ability, and therefore can’t diffuse through the cell membrane.

What happens if you take too many fat soluble vitamins?

This is why when a person takes too much of a fat-soluble vitamin, they can have too much of it present in their body over time. This is potentially dangerous, and is called hypervitaminosis. When there is an excess of these vitamins in your body, it simply passes through your body.

For example, the antibiotic rifampin, a highly fat-soluble drug, rapidly enters the brain, but the antibiotic penicillin, a water-soluble drug, does not. In general, fat-soluble drugs can cross cell membranes more quickly than water-soluble drugs can.

Any excess of water-soluble vitamins, like the Vitamin B complex or Vitamin C, are excreted through the urination process. Many B vitamins and Vitamin C can be found in vegetables (like leafy greens and other green vegetables) and fruits (like citrus fruits). Fat-soluble vitamins dissolve in—you guessed it—fat.

This is why when a person takes too much of a fat-soluble vitamin, they can have too much of it present in their body over time. This is potentially dangerous, and is called hypervitaminosis. When there is an excess of these vitamins in your body, it simply passes through your body.

Why are lipid-soluble substances harder to dissolve in water?

Urine is watery and kidney’s excrete water through ion homeostasis. Hydrophobic compounds do not dissolve in water and hence cannot be excreted by the kidneys. The liver has an important role in making hydrophobic toxins water-soluble.