Nonlinear and Phenytoin Math - Amin

A physician asks your assistance. The patient is a 6’1” tall, 90 kg man admitted to the hospital for seizures. The physician wishes to achieve a plasma concentration of 12 mg/L. Calculate a loading dose of IV fosphenytoin. (Round to the nearest whole numeber)

• 205 mg

• 756 mg

• 822 mg

• 540 mg
• 300 mg

A physician asks for your assistance. The patient is a 5’8” tall, 80 kg woman admitted to the hospital for new-onset seizures. The physician wishes to achieve a plasma concentration of 15 mg/L. Calculate a loading dose of IV fosphenytoin. (Round to the nearest whole number)

• 913 mg

• 782 mg

• 694 mg

• 730 mg

• 840 mg

A 78 kg male, 6’0”, is admitted after multiple seizures. The target plasma concentration is 10 mg/L. Calculate an appropriate loading dose using phenytoin for this phenytoin naive patient. (Round to the nearest whole number)

• 593 mg

• 634 mg

• 546 mg

• 612 mg

• 482 mg

A 63 kg woman is newly diagnosed with epilepsy and needs a loading dose of phenytoin. The physician wants to achieve a concentration of 12 mg/L. Calculate the required loading dose. (Round to the nearest whole number)

• 428 mg

• 575 mg

• 546 mg

• 529 mg

• 479 mg

A 8.9 kg 9 month old male is newly diagnosed with epilepsy and needs a loading dose of phenytoin sodium. The physician wants to achieve a concentration of 10 mg/L. Calculate the required loading dose.

• 106.8 mg

• 127 mg

• 67 mg

• 62 mg

• 118 mg

A 60 kg woman has been receiving 320 mg/day of phenytoin sodium for 8 days. Her phenytoin levels today are 11 mg/L. Would you expect her to be at a steady state? (Select the most appropriate answer rounding to the nearest whole number)

• Yes, she is at steady state.
• No, She won't reach steady state till 12 days

• No, She won't reach steady state till 20 days

• No, she won't reach steady state until 22 days

• No, she is not at steady state till 16 days

A 67 kg woman has been receiving 300 mg/day of phenytoin for 7 days. Her phenytoin levels today are 8 mg/L. Would you expect her to be at a steady state? (Select the most appropriate answer rounding to the nearest whole number)

• Yes, she is at steady state.
• No, She won't reach steady state till 10 days

• No, She won't reach steady state till 12 days

• No, she won't reach steady state until 15days

• No, she is not at steady state till 8 days

A 70 kg male has been receiving 350 mg/day of phenytoin for 10 days. His phenytoin levels today are 10 mg/L. His albumin is 2.4 g/dL, levels were drawn at 25°C. Is the patient at steady state? (Select the most appropriate answer rounding to the nearest whole number)

• Yes, she is at steady state.
• No, She won't reach steady state till 18 days

• No, She won't reach steady state till 20 days

• No, she won't reach steady state until 25 days

• No, she is not at steady state till 32 days

A 65 kg male has been receiving 400 mg/day of phenytoin sodium for 9 days. His phenytoin levels today are 7 mg/L. His albumin is 2.1 g/dL, levels were drawn at 37°C. Is the patient at steady state? (Select the most appropriate answer rounding to the nearest whole number)

• Yes, she is at steady state.
• No, She won't reach steady state till 19 days

• No, She won't reach steady state till 20 days

• No, she won't reach steady state until 25 days

• No, she is not at steady state till 28 days

A 70 kg man has been receiving 310 mg/day fosphenytoin. When would you expect the patient’s phenytoin to reach steady state? (Round to the nearest whole number and select the best answer)

• This patient won't reach steady state till 4 days

• This patient won't reach steady state till 6 days

• This patient will never reach steady state

• This patient won't reach steady state till 8 days

• This patient won't reach steady state till 10 days