Question

5-fluorouracil is absorbed by

• A. Passive diffusion
• B. Active transport
• C. Pinocytosis
• D. Ion pair absorption

Hint:

For many lipophilic drugs like 5-fluorouracil, passive diffusion is the key absorption mechanism due to the concentration gradient.

Answer 1

The Correct Option is A

Step 1: Understanding 5-fluorouracil absorption.
5-fluorouracil, a chemotherapeutic agent, is absorbed primarily via passive diffusion, which occurs due to its lipophilic properties and concentration gradient across cell membranes.
Step 2: Analyzing the options.
(1) Passive diffusion: Correct — Passive diffusion is the most common mechanism for absorption of 5-fluorouracil.
(2) Active transport: Incorrect, 5-fluorouracil does not require energy or a carrier for absorption.
(3) Pinocytosis: Incorrect, this is not a typical mechanism for absorption of 5-fluorouracil.
(4) Ion pair absorption: Incorrect, 5-fluorouracil does not rely on ion pair absorption.
Step 3: Conclusion.
5-fluorouracil is absorbed by (1) Passive diffusion.