Heroin: What is it?






Street names/other names: Big H, Blacktar, Brown sugar, Dope, Horse, Junk, Muc, Skag, Smac, Caballo (Spanish), TNT, 8-ball (heroin mixed with cracked cocaine)

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Sunday, May 11, 2014

Hair Follicle Testing

          

Metabolites or circulating drugs may be detected in hair. First, these are deposited in the hair follicle and as the hair grows out, the metabolites will get trapped on the hair shaft and then in the keratin matrix. Drugs may also enter the hair through sweat, oil or the external environment. A 3-cm hair specimen may be able to indicate whether or not the person has been abusing drugs in the past 3 months. It is recommended that the hair specimen must be approximately 1.5 inches for drug abuse testing. When a person takes a drug, it takes approximately 4 to 5 days for the affected shaft to grow. However, there are a lot of factors that may affect the levels of the drug incorporated in a person’s hair. This means that high levels do not necessarily mean a more frequent drug abuse. It was demonstrated by Rothe et al that the doses of administered heroin and the measured concentration of opiates from the hair specimen were not correlated. The drug purity, metabolism, frequency of abuse and hair color are the factors that may affect the drug or metabolite amount incorporated in hair.




Natural hair color is an important factor in evaluating drug concentration. Drugs or metabolites are less incorporated in white fibers as compared with the pigmented ones. Melanin contains eumelanin which is accountable for hair with the colors black or brown whereas pheomelanin is responsible for red-colored hair. Drugs tend to bind less to pheomelanin than in eumelanin. Low abuse of drugs might not be detected in treated hair (e.g. bleached, permed or dyed). However, it can be detected in regular drug abuse but with reduced concentrations. Bleached or chemically-treated hair is more at risk to environmental drug uptake. Drugs already incorporated in hair are less removed in shampooing but this is effective in removing drugs absorbed from the environment. In hair follicle drug testing, heroin abuse can be detected as long as 90 days prior to testing.






COLLECTION AND TESTING


Hair sample is obtained and tested under the guidelines of the Society of Hair Testing. First, hair is thoroughly washed with the use of an organic solvent and with water subsequently. The washes can also be tested for the presence of the drug and its metabolites. After washing, the hair is cut into pieces and a small part is to be tested using Enzyme-linked Immunosorbent Assay (ELISA).



Quantity of hair needed



For this test, approximately 50 to 80 strands (45 mg) of hair are needed. There is slight variation due to hair color, thickness and texture. Samples obtained directly from hair comb or brush may not be used as samples should be taken live from the patient by cutting the hair strand as close to the scalp as possible.






ADVANTAGES

·         Hair follicle testing is reliable and accurate. It is considered to be better than urine testing as some drugs and their metabolites are easily flushed out of the bloodstream (3-7 days) whereas drugs trapped in the hair follicle for months to years.

·         It provides complementary information about the long-term drug abuse history of the patient.

·         Collection is non-invasive and the drugs incorporated in the hair have longer stability and they are bound for a long time.

·         Some people try to avoid hair follicle drug testing by going bald but avoidance is not possible since body hair can be used as a specimen as well.

·   The minimum concentration of metabolites that can be detected in hair follicle testing is low. Opiates trapped in hair with a concentration of only 100 pg/mg can be detected by using this test.

·         It can detect the following drugs: Cocaine (Cocaine & Benzoylecgonine), Marijuana, Opiates (Codeine, Morphine & 6-Monacteyl Morphine), Methamphetamine (Methamphetamine/Amphetamine & Ecstasy), and Phencyclidine (PCP).


DISADVANTAGES

·         Costly and time-consuming (minimum of 1 month)

·         It should be performed inside the laboratory

·         There are no available on-site testing kits

·         It cannot detect very recent drug abuse (1 to 7 days before testing)

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REFERENCES

Heroin and Your Veins: The Incredibly Disgusting Story (Cobb, A.)

A Health Educator’s Guide to Understanding Drugs of Abuse Testing (Dasgupta, A.)

Evaluation of Saliva/Oral Fluid as an Alternate Drug Testing Specimen (Crouch et al.)
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