Describe the major mechanisms of absorption and distribution of alcohol .updated 2023

1.  Describe the mechanisms of absorption and distribution of alcohol. What are the paths of absorption?

What factors increase or decrease the rate of absorption? 250 words 1 source

2. What are the major physiological and psychological effects of opiate drugs?

250 words

How is Alcohol Absorbed into the Body?
Ethanol is absorbed through the GI tract

When alcohol is consumed, it enters the stomach, where it can be absorbed into the bloodstream. However, if no food is present, most of the alcohol moves down into the small intestine where there is a much larger surface area for absorption compared to the stomach. The cells that line the stomach and small intestine (part of the gastrointestinal or GI tract) are called epithelial cells. These cells are perfect for absorption because they have finger-like projections protruding into the GI lumen, which tremendously increases the surface area for absorption of nutrients and other molecules through the membranes.

If one drinks alcohol with food in the stomach, the pyloric sphincter separating the stomach from the small intestine closes to allow the food to be digested by stomach acid. Since the alcohol can’t move into the small intestine immediately, this slows the absorption of alcohol into the bloodstream considerably. In fact, a fatty meal can reduce the peak blood alcohol concentration (BAC) up to 50% relative to that produced when alcohol is consumed on an empty stomach.

Most alcohol absorption into the body happens in the small intestine. The presence of fatty food can significantly slow the absorption of alcohol into the bloodstream.


Alcohol moves from the gut to the capillaries

To be absorbed, alcohol moves across the epithelial cells, through the interstitial space, and into the capillaries. The capillaries are made of endothelial cells. As alcohol moves through each of these cells, it moves in the direction of the concentration gradient.

Factors affecting drug absorption.
  • Movement of unchanged form of drug molecules from site of administration to systemic circulation is called absorption.

  • Various factors affect the rate of absorption they are listed as follows,

    1. Physico-chemical, 

    2. Pharmaceutical and,

    3. Physiological.

  1. Drug solubility and dissolution rate

  2. Particle size and effective surface area

  3. Polymorphism and amorphism

  4. Pseudo polymorphism (hydrates / solvates).

  5. Salt form of the drug.

  6. Lipophilicity of the drug – (pH partition hypothesis)


  1. Disintegration time (tablets / capsules).

  2. Dissolution time.

  3. Manufacturing variables.

  4. Pharmaceutical ingredients (excipients / adjuvants).

  5. Nature and type of dosage form.

  6. Product age and storage conditions


Order an assignment through this link:



1 . Jones, A. W. (2010). Absorption, distribution, metabolism, and elimination of alcohol: Highway to death. Alcohol, 44(6), 551-555. doi: 10.1016/j.alcohol.2010.08.005


 2 .Roehrs, T., & Roth, T. (2001). Sleep, sleepiness, sleep disorders, and alcohol use and abuse. Sleep medicine reviews, 5(4), 287-297. doi: 10.1053/smrv.2001.0162