Phenytoin Is a Weakly Acidic Drug with a PKa of 8.3

question 4

Multiple Choice

Phenytoin is a weakly acidic drug with a pKa of 8.3. Assume that the urine has a pH of 6.2. To what degree will phenytoin be ion trapped in the urine?

• A) extensive ion trapping
• B) moderate ion trapping
• C) no ion trapping
• D) insufficient data provided
• E) none of the above

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