A hair follicle drug test analyzes a small sample of hair to detect drug metabolites incorporated into the hair shaft from the bloodstream. Unlike tests that capture only a brief moment in time, this technique provides a historical profile of substance use. Employers, legal entities, and individuals frequently use this method to gain a comprehensive history. The process begins with sample collection at a certified location, with the sample then being sent to a laboratory for analysis.
Unique Characteristics of Hair Follicle Testing
Entities often select hair follicle testing because it provides a longer detection window compared to more common methods like urine or oral fluid testing. The drug metabolites circulating in the blood become permanently trapped within the hair shaft as the hair grows. For standard scalp hair, which grows at an average rate of about one-half inch per month, a typical 1.5-inch sample can reflect a history of substance use stretching back approximately 90 days.
This methodology offers a significant forensic advantage due to its resistance to manipulation or tampering. Because the collection is performed under direct supervision, the likelihood of sample substitution is nearly eliminated. Furthermore, drug compounds are chemically bonded within the keratin structure of the hair, meaning they cannot be simply washed out or diluted with external products. This inherent stability makes the results highly reliable for evaluating past patterns of use.
Primary Testing Locations and Providers
Individuals and organizations seeking a hair follicle drug test must utilize specialized collection sites connected to accredited laboratory networks. The most common providers are national diagnostic laboratories, such as Quest Diagnostics and LabCorp, which operate extensive networks of patient service centers across the country. These large-scale providers handle the majority of employer-mandated testing programs, offering standardized collection procedures and laboratory analysis.
For personal or legal purposes, testing can be accessed through specialized drug testing clinics and walk-in health facilities, including certain urgent care centers. These facilities act as third-party collection sites for the major laboratories. This allows a person to order a test online or over the phone and then be routed to a nearby collection location. This system effectively separates the ordering process from the physical collection, offering a streamlined approach for non-corporate testing needs.
Hospital occupational health services also provide collection for hair testing, often serving local businesses that require pre-employment or random drug screening. While the sample collection occurs at these diverse locations, the actual analysis is performed at centralized, certified laboratories. Distinguishing between mandated testing and self-ordered testing is important, as corporate programs are strictly scheduled, whereas personal tests can often be arranged at a collection site with short notice.
Preparing for the Test and Understanding the Timeline
Once a testing location is selected, preparation is relatively simple, as no special steps are required to ensure the accuracy of the test. Claims that special shampoos or hair treatments can remove drug metabolites are inaccurate because the compounds are embedded within the hair structure, not just on the surface. Donors should arrive with their hair clean and dry, although prior washing or styling does not affect the outcome of the analysis.
During the collection process, the collector requires approximately 100 milligrams of hair, which is about 90 to 120 strands, cut as close to the scalp as possible. This sample is usually taken from the crown of the head to ensure the freshest growth and is then secured in foil and sealed with official documentation. If the individual has insufficient scalp hair, the collector may take a sample of body hair, such as from the chest, armpit, or leg.
The timeline for receiving results begins once the sample arrives at the laboratory, not at the time of collection. For samples that screen negative for all substances, results are reported quickly, often within 48 to 72 hours of the lab’s receipt. If the initial screening test yields a presumptive positive result, the sample must undergo a second, more precise confirmation test using advanced technology like mass spectrometry. This secondary analysis can extend the total turnaround time, meaning a final confirmed result may take up to five business days.