Question 1

During pregnancy,drug absorption from the gastrointestinal tract is variable and unpredictable due to slowed peristalsis and gastric emptying.

Accepted Answer

This statement is true. The hormonal changes during pregnancy can slow down the digestive system, which can affect the absorption of drugs taken through the gastrointestinal tract. This can lead to variable and unpredictable drug levels in the bloodstream.

Question 2

Which one of the following factors would not be expected to increase the rate of drug absorption from the small intestines?&#10;A) A small-sized drug molecule&#10;B) Delayed gastric emptying&#10;C) An increase in gut blood flow&#10;D) The majority of drug molecules in an un-ionised state

Accepted Answer

Delayed gastric emptying would not be expected to increase the rate of drug absorption from the small intestines. This is because delayed gastric emptying slows down the movement of food and drugs from the stomach to the small intestine, resulting in a longer time for absorption to occur. Therefore, option B would not increase the rate of drug absorption. The other options - A, C and D - are all factors that would increase drug absorption from the small intestine. Small-sized drug molecules will increase the surface area available for absorption, an increase in gut blood flow will increase the supply of nutrients and oxygen to the intestinal cells responsible for absorption, and the majority of drug molecules in an un-ionised state will increase the lipophilicity of the drug, allowing it to diffuse more easily across cell membranes.

Deck 19: Pharmacokinetic Factors That Modify Drug Action