Nail testing FAQs

How does nail drug testing work?

Nail analysis can provide detailed information about drug consumption.

Any drug that is consumed circulates in the bloodstream and a proportion of it and its metabolites become incorporated into the keratin that makes up nails. This tough, fibrous protein traps any drugs and their biomarkers ready for detection. Keratin is also the main structural constituent of hair. Therefore, both hair and nail drug testing can detect the same drugs.

nail drug sample

In addition, the turnaround times for both testing methods are similar. A major difference, however, is that head hair grows at a regular rate (approximately 1 cm a month) so samples can be used to show a pattern of drug use. For example, with a sufficient hair sample, a month-by-month analysis of the donor’s drug usage can be obtained for a period of several months.

This type of segmenting can’t be done with nail clippings, but they can give an overview and can detect drugs for up to 12 months after ingestion.

What drugs can be detected in a nail drug test?

Nail testing can be used to test for the following drugs:

Methamphetamine Ketamine
Amphetamine Mephedrone
Benzodiazepines Methadone
Cannabis Opiates
Cocaine Zolpidem
Ecstasy (MDMA)

Does it matter which nail is used for the test?

Either fingernails or toenails can be used for the test, but not a mixture. Approximately 10 mg of nail is required in total.

How are the samples collected?

Nail clippings need to be taken as near to the nail bed as possible. Approximately 10 mg of nail is required for the test. The nail is collected as close to the nail bed as possible. If the nail is long (5 mm or above) then only one would be required. If the nails are short then it may be best to take clippings from several nails.

Toe nails as well as finger nails can be used, but not a mixture of both. The advantages of using toe nails is that there is less potential for environmental exposure. Acrylic nails, Shellac and other forms of nail varnish would need to be removed as this may damage the surface of the nail and impact on the drug results.

Nail clipping samples would need to be collected under chain of custody conditions to support legally defensible results. This would require either an appointment with one of our trained sample collectors at a place convenient to the donor or at our Dublin Walk-in-Centre.

How long does it take to get the results from my nail drug test?

The standard turnaround time is 3–5 working days.

Will false nails affect the result?

As well as being in the nail itself, drugs are incorporated in the nail bed which is underneath the nail so the results would not be affected by false nails.

Will nail varnish, Shellac and acrylic nails need to be removed?

Acrylic nails, Shellac and other forms of nail varnish will need to be removed. As this may damage the surface of the nail it could impact on the drug results.

What is the window of detection for drugs in nails?

Drugs can be detected for 3–6 months after ingestion.

What will the results of the nail drug testing tell me?

We can test for up to 11 drugs. The test results will tell you which of the following drugs has been ingested and over how many months: methamphetamine, amphetamine, mephedrone, benzodiazepines, opiates, methadone, cannabis, zolpidem, ketamine, cocaine, ecstasy (MDMA).

How long will the drug stay in the nail?

Drugs and their biomarkers become locked in keratin fibres along the entire length of the nail, and can be detected up to 3–6 months after drug abuse.