In most cases, cocaine does not remain in one’s system very long, especially when it is the only drug taken. The half-life of the drug represents the amount of time it takes for levels of the drug to be reduced by half of their original concentration. The half-life of cocaine is very short. According to one study, the average half-life of cocaine in blood is about 1.5 hours, in saliva is about 1.2 hours, and in urine is about 4.1 hours. Cocaine typically is detectable in urine
for one day after use.
The primary organ responsible for breaking down cocaine in the body is the liver. This process is known as metabolism, where enzymes transform the substance into other compounds called metabolites that are easier to eliminate from the body. The major metabolite for cocaine is called benzoylecgonine, and it is often measured in urine drug testing since it is detectable for a longer period of time after cocaine use than cocaine itself is.
Benzoylecgonine has a half-life of about 12 hours, and it is typically detectable in urine for two to three days after the most recent use of cocaine. However, chronic users of cocaine may have detectable levels of the drug and/or its metabolites in their bodies for longer than average periods due to accumulation of cocaine in the body. A urine drug screen for cocaine and its metabolites may be positive for up to two weeks after last use in heavy users.
General timelines for the detection of cocaine and/or its metabolites in the body can be estimated as:
- Cocaine or its metabolites can be detected in saliva for about one to two days after last use.
- Cocaine can be detected in blood samples for about 12 hours after last use. Benzoylecgonine can be detected in blood for about 48 hours after last cocaine use.
- Cocaine metabolites can usually be detected in urine samples for 2-3 days after last use. However, urine drug tests might be positive for up to two weeks after last use for heavy cocaine users.
- Cocaine can be detected in perspiration for up to a few weeks after last use.
- Hair samples may have detectable levels of cocaine for months and even years after last use.
The length of time that cocaine will remain in a person’s system depends on a number of factors.
All of the above figures are estimates. There are several elements that can influence the amount of time it will take a person’s body to eliminate cocaine. These include:
- The amount of cocaine used and how long it has been used for: As mentioned above, individuals who use cocaine chronically and in greater amounts may have traces of cocaine and/or its metabolites in their systems for longer periods of time.
- The purity of the cocaine: If there are significant differences in the purity of the cocaine, it could result in different elimination times from the body since it could contain drastically different amounts of actual cocaine.
- Individual differences in metabolism: Genetics, age, gender, and some physical health issues may also influence the metabolism of cocaine and thus the amount of time that cocaine and/or its metabolites remain in the body.
- Other substances consumed: Medications, alcohol, and other chemicals consumed may speed up, slow down, or otherwise alter the body’s processing of cocaine, which could impact how long cocaine and/or its metabolites remain in the body.
Mixing Cocaine with Alcohol
Using cocaine and alcohol at the same time is a dangerous practice that can result in potentially fatal consequences. When cocaine and alcohol are used together, the combination results in a cocaine metabolite that remains in the body for a lengthier period of time.
When cocaine and alcohol are used together, a new metabolite called cocaethylene is formed in the liver and circulates in the body. Cocaethylene has a plasma half-life that is three to five times longer than that of cocaine, and it is linked to liver damage, seizures, and impaired immune system functioning. Cocaethylene has an 18- to 25-fold higher risk of immediate death than cocaine alone.
Furthermore, alcohol may increase the peak concentration of cocaine by about 20%, and cocaethylene presence is linked to higher mean blood alcohol concentrations. These synergistic effects are dangerous and can cause more adverse effects.
Mixing Other Drugs with Cocaine
There are a number of documented dangers regarding mixing cocaine with other drugs, such as opioids, cannabis, and nicotine. Mixing cocaine with heroin (also known as “speedballing”) or with other opioids increases respiratory depression and heightens the risk of overdose. Cannabis use with cocaine may increase the blood concentration of cocaine, thereby increasing the dangerous effects of cocaine. Both cocaine and nicotine can cause the coronary arteries to constrict, so when they are used together the risk of heart complications increases.
There does not appear to be a large body of literature that investigates if the elimination process of cocaine is significantly affected by the presence of other recreational drugs in the system (besides alcohol). However, several drugs of abuse can cause liver damage over time, which it turn may impede the ability of the liver to metabolize other drugs, such as cocaine.
Furthermore, there are medications, supplements, and foods that may speed up or slow down the body’s metabolism of cocaine through their effects on the enzymes CYP3A4 and CYP3A5, which is involved in the metabolism of cocaine. Examples include erythromycin, grapefruit juice, and St. John’s Wort.
Although the effects of many drugs on the elimination of cocaine are not clear, there are several that are more dangerous in combination with cocaine than either alone.