Question

The​ concentration, C, of​ phenylbutazone, in micrograms per milliliter ​(​g/ml), in the plasma of a calf injected with this​ anti-inflammatory agent is given approximately by ? (where t is the number of hours after the injection and C0 is the initial concentration.

a. C(t)=C0e^(−kt)
b. C(t)=C0e^(kt)
c. C(t)=C0e^(k^2t)
d. C(t)=C0e^(−kt^4)

Answer 1

The formula representing the concentration of phenylbutazone in the plasma of a calf post-injection is C(t) = C0e^(-kt), signifying an exponential decrease over time due to first-order kinetics.

Step-by-step explanation:

The concentration, C, of phenylbutazone, in micrograms per milliliter (µg/ml), in the plasma of a calf injected with this anti-inflammatory agent is given approximately by the formula C(t) = C0e^(-kt), where t is the number of hours after the injection, C0 is the initial concentration, and k is a constant that represents the rate of elimination of the drug from the plasma.

Pharmacokinetics studies focus on the behavior of drugs within the body, considering factors like concentration over time. The given formula represents the exponential decay of drug concentration, meaning as time passes, the concentration of the drug in the plasma decreases exponentially. This is a characteristic of drugs that are eliminated from the body at a rate proportional to their concentration, which is known as first-order kinetics.