What is a common route of administration for 5-fluorouracil when used as an anti-cancer agent?

What is a common route of administration for 5-fluorouracil when used as an anti-cancer agent?

• A. Oral
• B. IV
• C. Subcutaneous
• D. Topical

Answer: (B)

Intravenous administration is the standard route for systemic chemotherapy with 5-fluorouracil. This drug has a very short half-life and is rapidly cleared, so delivering it by IV allows clinicians to achieve and maintain effective plasma levels that maximize tumor exposure. IV infusion, often continuous, provides precise control over dosing and helps balance efficacy with toxicity. Oral 5-fluorouracil is not ideal for systemic cancer treatment because it has poor and highly variable bioavailability due to extensive first-pass metabolism, leading to unpredictable blood levels. Topical 5-FU is used for skin conditions and superficial lesions, not for treating deeper or systemic cancers, because it doesn’t achieve the necessary systemic exposure. Subcutaneous administration is not the standard approach for typical systemic regimens.

Intravenous administration is the standard route for systemic chemotherapy with 5-fluorouracil. This drug has a very short half-life and is rapidly cleared, so delivering it by IV allows clinicians to achieve and maintain effective plasma levels that maximize tumor exposure. IV infusion, often continuous, provides precise control over dosing and helps balance efficacy with toxicity.

Oral 5-fluorouracil is not ideal for systemic cancer treatment because it has poor and highly variable bioavailability due to extensive first-pass metabolism, leading to unpredictable blood levels. Topical 5-FU is used for skin conditions and superficial lesions, not for treating deeper or systemic cancers, because it doesn’t achieve the necessary systemic exposure. Subcutaneous administration is not the standard approach for typical systemic regimens.