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Hair Drug Screening Test

Updated: Jun 30

A drug screening test is a scientific analysis that can be used to detect the presence of drugs in a person's body. It requires a small amount of the person's hair to be sent to the laboratory for results in a few days. The hair drug screening test is a quantitative analysis. This means it can determine the amount of drug ingested during the three months prior to the test.

dépistage de drogue

How to Perform a Hair Drug Screening Test?

Hair drug screening tests are becoming increasingly popular as a means of measuring a person's drug consumption.

Unlike urine or blood tests, which can only detect recent drug use, hair tests can detect consumption dating back several months. They are therefore an ideal way to check for long-term drug use and identify drug consumption patterns. The most common method for detecting the presence of drugs in hair involves taking a small hair sample and sending it to a laboratory for analysis. The laboratory then looks for the quantity of drugs in the hair.

It's important to note that hair drug screening tests are generally more expensive than other types of tests, but they are also more accurate.

Indeed, drugs and their metabolites are stored in hair follicles, and as hair grows, these traces are pushed to the surface of the hair shaft. Therefore, a hair test can provide an accurate picture of a person's drug consumption over a period of several weeks or even months.

Additionally, hair tests are less likely to be affected by factors such as sweat or shampooing, making them more reliable than other types of drug screening tests.

To perform a hair drug screening test, a small hair sample (3 cm in length) is taken from the subject's head or body (for body hair: 1 cm). The hair is then sent to a laboratory, where it is analyzed to detect the presence of substances and the quantity.

The hair test cannot tell you when the drug intake occurred or the frequency, but only the amount detected in the sampled hair. It's important to note that depending on the rate of hair growth, in some individuals, the analysis may detect substances that were ingested before the three months but appear in the hair within the three months before the sampling.

Advantages of the Hair Test

The hair test is a reliable and anonymous method for screening drug consumption. The test is conducted in an ISO 17025 certified laboratory, and the results are entirely tamper-proof.

The test can detect any drug consumption in the last 90 days, and its reliability exceeds 99.9%. The hair test is also a convenient way to screen for multiple drugs at once. Up to four drug families can be screened simultaneously, making it a quick and easy way to obtain accurate results.

Which drugs can be detected?

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This test detects the most common drugs: cannabinoids, cocaine, opioids, and amphetamines. For each category, the test measures the exact quantity of substance found in the hair. This provides a more accurate picture of drug consumption over time. Detected cannabinoids include all cannabis derivatives, such as marijuana and hashish. Detected cocaine includes all cocaine derivatives like crack. Detected opioids include all opium derivatives, such as heroin, codeine, and morphine. Detected amphetamines include all amphetamine derivatives, like speed, ecstasy, and methamphetamine.

Nicotine Detection:

While most drug screening tests focus on detecting illegal substances, it's also possible to test for nicotine or alcohol consumption.

Nicotine is a highly addictive substance found in tobacco products: cigarettes, cigars, and chewing tobacco. Although it's possible to become addicted to nicotine through other means, such as patches or gum, smoking is by far the most common method. By conducting nicotine screening tests, you can easily determine if your children are smoking, even if they show no signs of addiction.

Why Hair Testing?

Hair is often considered a good indicator of drug consumption because it can reveal drug metabolites that have deposited in the scalp over time. Drug metabolites are chemicals produced when the body breaks down drugs.

They can be detected in hair up to 90 days after drug consumption, making the hair test an effective way to screen for long-term drug use.

Additionally, hair tests are less invasive than other types of drug screening tests, such as urine or blood tests. This makes them an appealing option for employers and others who want to screen for drug use without infringing on the privacy of those being tested.

How Much Hair is Needed and in What Condition?

To determine the amount of hair needed for the test, 70 to 100 hairs are required. Hair color does not interfere with the test quality. This test can be performed on all hair types, including colored, bleached, or permed hair. The analysis can be done with hair longer than 3 cm for detection up to 90 days. The detection is 30 days per centimeter of hair. If the hair is less than 3 cm, the detection will be lower.

The first traces may appear after about 4 to 6 days after taking a substance. However, there's no one-size-fits-all reaction, and each metabolism is different regarding detection. It's therefore best to consider a minimum of 10 days before a drug can be detected in the samples.

How to Legally Drug Test with a Doctor?

If you're required to undergo a legal drug screening test, you need to keep a few things in mind. First, it's crucial to always follow the instructions regarding sample collection. For a legal test, the person's identity must be verified by a sampler such as a doctor. Second, make sure to provide a list of all medications you're currently taking, as well as vitamins or supplements. By following these simple guidelines, you can ensure that your legal drug screening test goes smoothly and accurately reflects your current health status.

When to Screen and How Often?

Drug screening is a necessary but sometimes controversial step to ensure the safety of young individuals. When done correctly, it can help identify risky behaviors and provide children with the help they need to stay on the right path. However, drug screening can also be intrusive and invasive, raising privacy concerns. The key is to find the right balance, and that involves understanding when drug screening is appropriate.

Screening should generally be done within hours following typical drug consumption occasions, such as parties or festivals. This ensures that any risky behavior is identified and can be addressed before it becomes a problem. Of course, there will always be exceptions to this rule, but in general, swift screening is the best way to ensure the safety of children without violating their privacy.

To be effective, a screening program must have a high enough frequency to maintain a strong deterrent effect. Those who might be tempted to cross the line need to be convinced that the risks simply aren't worth it. The best way to achieve this is by maintaining a high level of visibility of the monitoring program. Random checks should be conducted regularly. Additionally, checks should be performed immediately after any event, to constantly remind young individuals of the risks involved. By keeping the frequency of checks high, we can ensure that individuals remain deterred from using prohibited substances.

Capillary Test for Chemical Submission: GHB

Chemical submission is a serious crime that can have devastating consequences on the victim's life. The administration of one or more psychoactive substances without the victim's knowledge or under threat can lead to a loss of control over their own body and mind. This can result in long-term physical and psychological problems for the victim, including memory loss, anxiety, and depression.

Chemical submission is often used as a tool for sexual assault or pedophilic acts, as it can incapacitate the victim and make them more vulnerable to attacks. It is also frequently used in robberies and other crimes where the perpetrator aims to subdue their victim.

Hair analysis is one effective method of detecting the presence of chemicals in the body that may have been used to facilitate rape or robbery. This type of test can specifically identify the presence of GHB or other sedatives and date the time of administration to within 10 days. This information can be vital in assisting an ongoing investigation. GHB is a potent drug due to its rapid elimination from the body; detecting GHB in the victim's system is challenging. Therefore, it's crucial for GHB victims to undergo testing as soon as possible after the incident. GHB screening can determine the date of the assault up to 10 days.

For a hair sample to be effective in this investigation, it is important to follow certain protocols. First, the sample must be taken at least six weeks after the presumed exposure to the substance in question. This is because the substance takes time to penetrate the hair follicle. If the sample is taken too early, there is a risk that it may not be accurate. Additionally, it's important to take a high-quality sample from an area of the head that has not been exposed to chemicals or other contaminants. By following these guidelines, it is possible to obtain a precise and reliable hair sample for testing.

Drug Families


Cannabinoids are the active compounds found in cannabis. They form a group of chemical substances that act on the cannabinoid receptors in the brain. There are over 100 cannabinoids, each with different effects depending on the receptor they bind to. Some cannabinoids are psychoactive, inducing a state of euphoria, while others are not. Cannabinoids interact with the body's endocannabinoid system, involved in various physiological processes such as pain, appetite, memory, and mood. The most well-known cannabinoid is delta-9-tetrahydrocannabinol (THC), the main psychoactive component of cannabis. Other cannabinoids, like cannabidiol (CBD) and cannabinol (CBN), also have psychoactive effects. Cannabinoids can be consumed in various forms, including smoking, vaporizing, ingestion, or using topical products.


While most people are familiar with cocaine, few know there are various derivatives of cocaine. These include ecgonine, an alkaloid present in the coca plant, and benzoylecgonine, the primary metabolite of cocaine. Ecgonine is also used to produce processed freebase cocaine, or "crack." Crack is a highly addictive form of cocaine produced by adding baking soda or ammonia to the drug. Crack is typically smoked for faster absorption into the bloodstream, increasing the risk of addiction and causing severe health issues. Cocaine derivatives are also used in medical procedures, including local anesthesia and vasoconstriction. However, using these drugs carries risks, including overdose and death.


Opiates are a category of drugs derived from opium, a substance extracted from the poppy plant. Well-known opiates include heroin, codeine, and morphine. These drugs are commonly used to treat pain by binding to the brain's opioid receptors. Opiates can lead to addiction and cause side effects such as drowsiness, constipation, and nausea. At high doses, they can slow down breathing and heart rate, potentially leading to death. Opiate addiction has become a serious problem in recent years, with many individuals who initially use opiates for pain relief becoming dependent. Treatment options are available to help overcome addiction and lead a healthy, drug-free life.


Amphetamines are a type of synthetic drug that stimulates the nervous system. They are commonly used as central nervous system depressants and are often prescribed to treat conditions such as ADHD and narcolepsy. However, amphetamines are also frequently abused for their psychoactive effects. When taken at high doses, they can produce feelings of euphoria, increased alertness, and energy levels. Amphetamines are highly addictive, and long-term use can lead to serious health issues, such as a heart attack or stroke. Methamphetamine, one of the most common amphetamines, is particularly dangerous due to its high potency and the risk of overdose. It's crucial to be aware of the risks associated with amphetamine abuse before taking these drugs.


Ketamine is an antidepressant that rapidly improves mood and thinking. Its use has been approved for treating major depression that hasn't responded to other treatments. In addition to its antidepressant properties, ketamine also has analgesic, anti-inflammatory, and neuroprotective effects. Common side effects include dizziness, headaches, nausea, and vomiting. When used in high doses or abused, ketamine can cause dissociation, hallucinations, and impairments in motor function and cognition. Long-term ketamine abuse can result in damage to the bladder, kidneys, and liver.


LSD is a powerful psychoactive substance used for centuries in religious and spiritual rituals, also known as acid. LSD acts on serotonin receptors in the brain, causing changes in perception, mood, and consciousness. Users often report feelings of euphoria, spiritual insights, and hallucinations. LSD can also induce anxiety and paranoia. The effects of LSD are unpredictable, varying based on the user's physiology, mindset, and environment. A bad trip can be a frightening experience. LSD is illegal in most countries, and its consumption carries the risk of imprisonment.


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