Nail Samples Show Wider History of Drug Use Than Urine

Nail samples provide an excellent alternative sample matrix to urine. Some drugs that do not bind well in hair, like marijuana, are very stable in a nail matrix. ProResults offers 5- 10-, 12- 14-, 17-, 18-, and 19-drug panels for nail samples.

Nail samples are a similar matrix to hair, a keratinized protein, and therefore can be tested similarly. Drugs enter nails through nail matrix cells located at the base of each finger or toenail. Drugs are then distributed down the nail bed into new layers of growth. Most people do not know that nails grow both in length and in thickness, with the free end of the nail being thicker than the lunula at the base of the nail. Drugs present on the nail bed are incorporated into these layers.

Drugs of abuse are measurable in nail samples approximately two weeks following ingestion.

Fingernail samples can reflect drug usage over a six-month period.

Toenails, growing at a slower rate, can identify drug usage in the previous 12-month period. Collecting either sample will give a much longer view of drug history than urine, oral fluid or blood. Nail testing also boasts a less demanding collection process than urine or blood.

Our Nail Drug Testing assay requires 100 milligrams of nail sample. The amount is equal to a 2 millimeter sample harvested from each finger.

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The laboratory test procedure includes an immunoassay initial test combined with

LC/ MS/MS or GC/MS confirmation of presumptive positive results.