Urine has always been an effective method of drug testing. However the test typically only reaches as far back as 9 to 10 days. On the other hand, Hair Testing can detect past months of usage.

The results below are based on companies of varying sizes and show the difference in the testing of urine and hair. American Toxicology believes that the best fingerprint of drug use is obtained by testing both hair and urine. The following illustrates the comparisons between hair and urine testing of four of our clients.

Company 1: # of total tests: 10,558

Drug……………….Pos/Urine…………..Pos/Hair
Amphetamines…………29…………………….158
Cocaine………………...256…………………...730
Heroin………………….0………………………...0
PCP…………………….1………………………...2

Company 2: # of total tests: 3,953

Drug……………….Pos/Urine…………..Pos/Hair
Amphetamines…………12………………………50
Cocaine………………...11…………………........28
Heroin………………….1…………………….…...1
PCP…………………….0………………………....0

Company 3: # of total tests: 209

Drug……………….Pos/Urine…………..Pos/Hair
Amphetamines…………0………………………....3
Cocaine………………...1…………………............7
Heroin………………….0…………………….…...1
PCP…………………….0………………………....0

Company 4: # of total tests: 52

Drug……………….Pos/Urine…………..Pos/Hair
Amphetamines…………0…………………………1
Cocaine………………...1…………………............3
Heroin………………….0………………………....0
PCP…………………….0………………………....0

Results indicate that hair and urine testing is far superior tot urine testing alone in identifying drug users attempting to become employed. Over 2/3 of the applicants testing positive by hair would have passed the urine test and became part of the employee population. Marijuana is not shown in this example because it is best detected in the urine.

Because it takes approximately a week for ingested drugs to show up in hair above the scalp, American Toxicology strongly suggests using both urine & hair testing for a complete history of drug usage to help maintain a drug-free work environment. Studies continue to show that marijuana (THC) is best detected in urine. THC is a fat soluble drug that stays in the body much longer than any of the hard drugs. As a result, the body will shed THC for weeks or even months. Once again, for optimal results American Toxicology strongly recommends a Hair & Urine test for all clients.

Detection periods

The following chart from LabCorp gives approximate detection periods for each substance by test type.^[1] The ranges depend on amount and frequency of use, metabolic rate, body mass, age, overall health, and urine pH. For ease of use, the detection times of metabolites have been incorporated into each parent drug. For example, heroin and cocaine can only be detected for a few hours after use, but their metabolites can be detected for several days in urine. In this type of situation, we will report the (longer) detection times of the metabolites.

• NOTE 1: Oral fluid or saliva testing results for the most part mimic that of blood. The only exception is THC. Oral fluid will likely detect THC from ingestion up to a maximum period of 18-24 hours
• NOTE 2: Urine can not detect current drug use. It takes approximately 6–8 hours or more post-consumption for drug to be metabolized and excreted in urine. Similarly, hair requires two weeks, and sweat, seven days.

Approximate values for detection periods

Substance	Urine	Hair	Blood
Alcohol	3–5 days via ethyl gluconoride (EtG) metabolite or 10–12 hours via traditional method	lifetime of hair	12 hours
Amphetamines (except meth)	1 to 2 days	up to 90 days	12 hours
Methamphetamine	2 to 4 days	up to 90 days	24 hours
Barbiturates (except phenobarbital)	2 to 3 days	up to 90 days	1 to 2 days
Phenobarbital	7 to 14 days	up to 90 days	4 to 7 days
Benzodiazepines	Therapeutic use: 3 days. Chronic use (over one year): 4 to 6 weeks	up to 90 days	6 to 48 hours
Cannabis	Light use: 2-7 days Prolonged use: 1-3 months	up to 90 days	12 days
Cocaine	3 to 300 days with exceptions for certain kidney disorders	up to 90 days	24 hours
Codeine	1 day	up to 30 days	12 hours
Cotinine (a break-down product of nicotine)	2 to 4 days	up to 90 days	2 to 4 days
Morphine	2 days	up to 90 days	6 hours
Heroin	2 days (single use) 2-5 (chronic)	up to 90 days	6 hours
LSD	2 to 24 hours	up to 3 days	0 to 3 hours
Methadone	3 days	up to 30 days	24 hours
PCP	14 days; up to 30 days in chronic users	up to 90 days	24 hours

This helpful information was provided by wikipedia.

Obviously the drugs remain longer in the hair follicle than they do any where else. American Toxicology recommends that both hair and urine drug testing be used for optimal results.