What percentage of inhaled nicotine is absorbed into the bloodstream?

The correct answer indicates that approximately 90% of inhaled nicotine is absorbed into the bloodstream. This high absorption rate can be attributed to several factors related to how nicotine is delivered when inhaled, particularly through smoking or vaping. When nicotine is inhaled, it rapidly enters the lungs, where it is absorbed through the alveoli—tiny air sacs that facilitate gas exchange. Given the large surface area and thin barriers of the alveoli, nicotine quickly travels into the bloodstream, leading to its swift effects on the body and brain.

This rapid absorption is significant because it contributes to the addictive nature of nicotine. Users experience immediate reinforcement as the substance reaches the brain within seconds of inhalation, which enhances its euphoric effects and can lead to repeated use. Understanding this process is crucial for addressing both the implications of nicotine use and the strategies for substance abuse treatment.