A vial of phenytoin sodium (Dilantin) contains 100 mg of drug in ...

[mcmcdaniel]

A vial of phenytoin sodium (Dilantin) contains 100 mg of drug in a total of 2 mL. How many milligrams of phenytoin sodium is contained in 0.5 mL of solution?
 
  a. 2.5 mL c. 25 mg
  b. 1.0 mg d. 50 mg

Question 2

A dose of 0.25 mg of a drug is equivalent to:
 
  a. 250 mcg. c. 2.5 mcg.
  b. 0.00025 mcg. d. 25 mcg.

[laurnthompson]

Answer to Question 1

ANS: C

Feedback
A Incorrect: This would yield 125 mg.
B Incorrect: This would be in 1/50 mL.
C Correct: Set up as a fractional dosage problem with 100 mg over 2 mL equals X over 0.5 mL = 25 mg.
D Incorrect: This would be in 1 mL.

Answer to Question 2

ANS: A

Feedback
A Correct: To convert 0.25 mg to mcg, multiply 0.25 mg by 1000 or move the decimal point to the right three places.
B Incorrect: The decimal point was moved three places to the left instead of three places to the right.
C Incorrect: The decimal point was moved only one place to the right.
D Incorrect: The decimal point was moved only two places to the right.

[mcmcdaniel]

Both answers were spot on, thank you once again

[laurnthompson]

Great! Please up vote