When you think about the active life of drugs, you probably think about how long you feel high. Scientists think of things a little differently.
To a scientist, a drug’s active life is measured by your metabolism. The moment at which half of the medication you’ve taken is removed is the drug’s active lifespan.
Your half-life might be different than the one experienced by someone who took the same drug. Metabolism can vary due to:
- Age. Our organs grow less efficient throughout their lifespan.
- Gender. Some drugs rely on fat cells, and women tend to have more than men.
- Race. Genes can dictate how quickly we metabolize some drugs, including alcohol, and they can be passed from parent to child.
- Weight. A bigger body has a larger amount of blood, and that can alter both intoxication and metabolism.
- Prior drug use. If your next hit happens when the last hit is still active, it might take longer for your body to catch up.
A scientist’s measurement of half-life is an approximation, based on studies of hundreds or even thousands of people. Your experience might be a little different, but the timeframes can be useful if you hope to understand how a hit you’re contemplating will change your body and your brain.
When scientists can’t determine a drug’s half-life (and some substances, including alcohol, just don’t work that way), they figure out the moment at which blood levels of the substance are at their highest. This is the time at which you’re likely to feel the most intoxicated, and from that point onward, sobriety is likely to return.
This is an approximation, but doubling the number could tell you how long you’re likely to feel intoxicated.