Cocaine: plasma concentrations after intranasal application in man.

Area of Science:

• Pharmacology
• Toxicology
• Drug Metabolism

Background:

• Cocaine is a potent stimulant with local anesthetic and vasoconstrictive properties.
• Understanding cocaine's pharmacokinetic profile after nasal administration is crucial for clinical and forensic contexts.

Purpose of the Study:

• To investigate the pharmacokinetic profile of cocaine following nasal mucosal application in human subjects.
• To determine the duration of cocaine presence in plasma and on the nasal mucosa.

Main Methods:

• Cocaine (1.5 mg/kg) was administered intranasally to human participants.
• Plasma concentrations of cocaine were measured over time.
• Residual cocaine on the nasal mucosa was assessed over a 3-hour period.

Main Results:

• Cocaine persisted in plasma for 4 to 6 hours post-administration.
• Peak plasma concentrations ranged from 120 to 474 ng/mL, occurring within 15 to 60 minutes.
• Detectable levels of cocaine remained on the nasal mucosa for up to 3 hours.

Conclusions:

• Intranasal cocaine administration results in prolonged systemic exposure.
• The sustained presence of cocaine on the nasal mucosa may contribute to its extended plasma persistence.
• Cocaine's vasoconstrictive effect might facilitate continuous absorption from the nasal mucosa.