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Cocaine Pharmacokinetics

Plasma concentration model for intranasal cocaine. The short half-life (~1.25h) is the pharmacological basis of the compulsion to redose — add multiple doses to see exactly why.

⚠ Test your substance. The majority of European cocaine samples contain levamisole (a veterinary antiparasitic associated with dangerous immune suppression with repeated use) and/or caffeine, phenacetin, or other cutting agents. Fentanyl contamination, while less common in Europe than North America, has been detected. A reagent test and fentanyl test strips are the minimum. Available from DanceSafe.
Population-average PK model. Individual variation in cocaine metabolism (via plasma cholinesterase and liver esterases) is significant. Cardiovascular risk zones are indicative — underlying heart conditions, stimulant tolerance, and concurrent substance use all shift risk substantially.

Personal details

kg

Dose schedule

First line
50mg
10mg200mg
Total: 50mg(0.71 mg/kg)
SHOW8h
0–100 ng/mL Low acute CV risk100–300 ng/mL Moderate — HR/BP elevated300–600 ng/mL High cardiac strain600–600+ ng/mL ⚠ Severe — arrhythmia/MI risk

Why cocaine is so compulsive — it's in the PK: With a half-life of ~1.25 hours, plasma concentration drops sharply within 1–2 hours. The rapid dopamine release followed by rapid crash creates a powerful neurobiological urge to redose before the previous line has cleared. Each additional line adds to cumulative cardiac load. Add 3–4 lines at realistic intervals and watch the curve — the heart is under continuous elevated stress.

Cardiovascular risk is cumulative: It is not just about peak concentration. Time spent above 100–300 ng/mL means sustained elevated heart rate and blood pressure. Cocaine-associated cardiac events occur across the full range of users, including young people with no known heart disease.

Dangerous combinations

Alcohol → CocaethyleneLETHAL RISK

When cocaine and alcohol are present simultaneously, the liver produces cocaethylene — an active metabolite that is more cardiotoxic than cocaine itself, has a half-life of ~5 hours (4× longer than cocaine), and is associated with sudden death. This is the most dangerous common drug combination by sudden cardiac death statistics. The combination feels more intense, which drives further use.

MDMA / amphetaminesSEVERE

Extreme combined cardiovascular strain. Both drugs elevate heart rate and blood pressure through different mechanisms — the combination is not additive but multiplicative in cardiac load. Hyperthermia risk is substantially increased.

Other stimulants (caffeine at high dose, pseudo/ephedrine)MODERATE

Additive cardiovascular stimulation. Caffeine is the most common cutting agent in cocaine — meaning the combination is unavoidable unless you test your substance.

KetamineMODERATE

Opposing CNS effects — cocaine stimulates, ketamine dissociates. Combined cardiovascular strain. The stimulant can mask how dissociated you actually are, leading to additional dosing of either substance.

CannabisLOW–MODERATE

Cannabis can mask cocaine-induced anxiety, leading to higher cocaine use than intended. Cardiovascular effects are additive. Combined impairment affects judgement about further use.

Levamisole (common adulterant)CHRONIC RISK

Levamisole is a veterinary antiparasitic found in the majority of European cocaine samples. With repeated exposure it causes agranulocytosis — dangerous immune suppression. Acute use carries low risk but chronic use with contaminated cocaine is associated with serious infections. Always test your substance.

Concerned about cocaine use? Jellinek.nl and Trimbos.nl offer free, confidential support.