When introduced into the body—whether by inhalation, snorting, oral intake, or intravenous injection—cocaine's absorption rate and the subsequent intensity of its effects are heavily influenced by the method of administration. Inhalation and intravenous routes lead to rapid absorption, delivering an immediate and potent high, whereas snorting results in a more gradual onset of the drug's effects. Once absorbed, cocaine swiftly distributes across various tissues, notably crossing the blood-brain barrier and the placenta, thereby impacting not just the user's brain but also, in cases of pregnancy, the fetus.
The metabolism of cocaine primarily occurs in the blood and liver, where plasma and hepatic esterases such as butyrylcholinesterase hydrolyze it to ecgonine methyl ester, while spontaneous hydrolysis yields benzoylecgonine. This transformation is crucial for the drug's eventual elimination from the body and plays a significant role in drug testing, as the presence of these metabolites in the urine is often used as evidence of cocaine use. Finally, the excretion of cocaine and its metabolites is chiefly carried out by the kidneys, allowing for their detection in not just urine, but also blood and hair samples.
