Complete Blood Count (CBC): What This Blood Test Measures and What Your Results Mean
A hair test that detects amphetamine use over an extended period, typically up to 90 days.
{"This test analyzes a hair sample to check for amphetamine use","It can detect drug use over the past weeks to months","Results are reported as positive or negative","Commonly used for workplace testing or legal purposes","Hair color, treatment, and growth rate may affect results"}
Key facts at a glance
- LOINC
- 40529-0
- Short code
- Amphetamines Hair Ql
- Synonyms
- Amphetamines Hair Ql
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
A complete blood count (CBC) is a common blood test that measures the cells circulating in your blood, including red blood cells, white blood cells, and platelets. Doctors use it to check your overall health and to screen for a wide range of conditions such as infections, anemia, and other blood disorders.
The Amphetamines Hair Test is a laboratory analysis that detects the presence of amphetamine drugs in a hair sample. Unlike blood or urine tests that show recent drug use (typically within days), hair testing can reveal drug exposure over a much longer period—usually up to 90 days or longer, depending on hair length.
A health care professional usually draws the blood sample from a vein in your arm using a small needle. After cleaning the site, the technician collects the blood into a tube and sends it to the laboratory. The procedure takes only a few minutes, and you can return to your normal activities right away.
A small hair sample, typically about 100-120 strands, is collected from the scalp. The hair is usually cut as close to the scalp as possible. The most recent 1.5 inches of hair closest to the root represents approximately the past 90 days of drug exposure. If head hair is not available, body hair may be used as an alternative.
The test measures red blood cells, which carry oxygen; white blood cells, which fight infection; hemoglobin and hematocrit levels; and platelets, which help your blood clot. Abnormal values can point to anemia, infection, inflammation, clotting problems, or blood disorders that may need further evaluation.
This test detects amphetamine and related substances including methamphetamine, MDMA (ecstasy), and other stimulants in the amphetamine family. The test uses sensitive laboratory methods to identify even small amounts of these substances that have been incorporated into the hair shaft through blood vessels.
Your report lists each measurement along with a reference range, which is the interval considered typical for healthy adults. Values slightly outside the range do not always mean illness, so your doctor will interpret the numbers together with your symptoms, medical history, and other tests. Contact your provider to discuss what your results mean for you.
Results are typically reported as either 'Positive' (substance detected) or 'Negative' (substance not detected). A positive result indicates that amphetamines were used during the time period represented by the hair sample tested. Your healthcare provider will help you interpret what these results mean in your specific situation.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Hair testing for amphetamines is commonly used in workplace drug screening programs, legal and forensic investigations, and substance abuse monitoring. It provides a longer detection window than urine or blood tests, making it useful for establishing a history of drug use rather than just recent exposure. In clinical settings, it may be used to monitor patients in substance abuse treatment programs or to assess compliance with abstinence requirements.
It's important to note that a positive result does not indicate impairment at the time of testing—it shows that amphetamines were used during the period represented by the hair sample. Factors such as hair treatment (bleaching, perming), hair color, and individual metabolism can affect test results, and confirmatory testing is typically performed if initial results are positive.
Frequently asked questions
How long can amphetamines be detected in hair?
Can hair products or treatments affect the test results?
Can secondhand exposure cause a positive result?
Will one-time use show up in a hair test?
Is this test legally admissible?
Sources
- 1
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Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy