One thousand micrograms of amphetamine taken orally is equivalent to:
A) 100 micrograms injected into the cerebrospinal fluid.
B) 10 micrograms injected into the cerebrospinal fluid.
C) 5 micrograms injected into the cerebrospinal fluid.
D) 1 microgram injected into the cerebrospinal fluid.

Question

Quizplus · Accepted Answer

The bioavailability of oral amphetamine is approximately 100%, which means that 1000 micrograms taken orally will result in 1000 micrograms circulating in the bloodstream. However, when amphetamine is injected into the cerebrospinal fluid, it bypasses the blood-brain barrier and has a significantly stronger effect. The ratio of oral amphetamine to cerebrospinal fluid amphetamine is approximately 1:100, which means that 10 micrograms injected into the cerebrospinal fluid is equivalent to 1000 micrograms taken orally. Therefore, the answer is B, 10 micrograms injected into the cerebrospinal fluid.

One Thousand Micrograms of Amphetamine Taken Orally Is Equivalent To