Phenytoin Requires That a Trough Level Be Drawn

question 4

Multiple Choice

Phenytoin requires that a trough level be drawn. Peak and trough levels are done:

• A) When the drug has a wide therapeutic range
• B) When the drug will be administered for a short time only
• C) When there is a high correlation between the dose and saturation of receptor sites
• D) To determine if a drug is in the therapeutic range

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Definitions:

Milliliters

A metric unit of volume equal to one cubic centimeter, used commonly in liquid measurement.

Apothecary Measurement

A historical system of weight and volume units used primarily by pharmacists for the compounding and dispensing of medications.

Equivalent

Equal in value, measure, force, effect, significance, etc. Often used in mathematical, scientific, and logical comparisons.

Apothecary Equivalent

A term referring to the system of weight and volume measurement used historically in pharmacies and the science of pharmacy.