Pharmacological and Parenteral TherapiesQuestion 2343 of 2368

A client who takes warfarin asks which vitamin can interfere with the effectiveness of the medication. Which vitamin should the nurse name?

  1. Vitamin B1 (thiamine)
  2. Vitamin B2 (riboflavin)
  3. Vitamin B9 (folic acid)
  4. Vitamin K
Show answer

Correct answer: Vitamin K

Vitamin K can interfere with the effectiveness of certain anticoagulants such as warfarin.

Source: Nursing Fundamentals, 2nd edition (Open RN, Chippewa Valley Technical College, 2024), Nutrition: VITAMINS. Licensed under CC BY 4.0.

Practice the topic "Pharmacological and Parenteral Therapies"

Questions last reviewed: 18 October 2026