This can be a tricky question, cocaine is rapidly metabolized by the body, usually within the first 24 hours after use. This happens because it is a water soluble substance. After a single use, between 48-96 hours after use the metabolite levels will be below the 300 ng/ml level for immunoassay testing. Therefore causing a negative result on the test. However, the GC/MS conformation cutoff is substantially lower at 150 ng/ml, that can test positive for a longer amount of time being as its more accurate type of testing. For 100% of metabolites to leave the body can and does take up to a possible 10 days. The way this happens is the body eliminates half of the concentration of the cocaine metabolite every 6.5 -9 hours. For example, 50,000 nanograms, after 8 or so hours would be 25,000, 8 more hours 12,500, and so on untill the levels drop off completely. Most studies do not reflect real world usage of cocaine, there are very few users that only dose a single time. Usually its multiple doses over an extended period of time. Long term use, and slow metabolism increase detection time. For cocaine to leave the body 100%....an educated guess would be anywhere from 8-12 days. Passing a urine test for cocaine, 4-7 days is a good rule of thumb. But again, everyones metabolism is different. Best advice is do not use, and stay clean.
