24/7 Drug of Abuse


By: Wyoming Pretrial Services SM


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True 24/7 Drug of Abuse Monitoring

We chose the PharmChek  Sweat Patch for its' ability to allow for the accurate and true 24/7 detection of drug use.

  • FDA Cleared, Patented Technology.
  • Standard (5), or Expanded Panels.
  • True 24/7 Round the Clock Drug Detection.
  • Increased Window of Detection.
  • Avoid Candidate Missed Tests, or Attempted Dilution.
  • No Urine Collection Required.
  • Detects Parent Drug, and Drug Metabolite.
  • Upheld for use in US Court of Appeals, 8th Circuit, 2007.
  • Tamper Resistant, with Zero Tolerance Policy.
  • Monitored by Certified Event Interventionist.

Frequently Asked Questions

24/7 Drug of Abuse Monitoring FAQs

How does the patch work

Worn on the candidates skin for a pre-set wear period.  The PharmChek® Sweat Patch captures insensible perspiration, the uncontrolled loss of sweat from the skin, in the absorbent pad.

Approximately 300-700 ml of insensible sweat is excreted each day, and about 2ml is absorbed in the patch each week.

The polyurethane film is a semi-permeable membrane that allows small molecules, such as oxygen, carbon dioxide, and water vapor to pass through the patch— leaving the skin underneath healthy and sterile.

Substances of large molecular weight are trapped in the absorbent pad of the patch and submitted to the laboratory for analysis.

May there be a positive result if a drug is not consumed 

Any “normal” constituents of sweat do not produce positive results. While drugs may be present in the environment, and even possibly present on skin surfaces, studies have not demonstrated (in realistic scenarios) that the transfer of such environmental drugs into sweat patches worn by these individuals would result in a positive analysis.

Detection Periods

Detection periods for the PharmChek® sweat patch must be thought about in terms that are a bit different from urine testing. The PharmChek® patch is a collection device designed to retain evidence of drug use for an extended period of time. That means that drugs excreted through sweat because of drug use at any time during the wearing of the patch will be collected, retained, and detected during analysis. For example: a PharmChek® patch were worn for 7 days it might be positive because of drug use on Day 1 or on Day 6.

Drugs and drug metabolites are excreted through bodily fluids over the course of about 48-72 hours. Therefore, if a subject used drugs yesterday and the PharmChek® patch is applied today, the subject's body is still excreting that drug out of their system when the patch is applied. This would result in a positive confirmation if both the parent drug and the metabolite are detected at or above the cut-off level at screening and confirmation. 

Can the patch be adulterated

Solvents, such as chloroform or acetone, have been applied to the covering of the PharmChek® patch. They bubble and shrivel the PharmChek® covering and evidence of adulteration is easily identified.

In order to adulterate the PharmChek® patch a substance must penetrate the outside covering of the patch. The only feasible method is to inject substances into the PharmChek® pad with a hypodermic needle. Part of the removal process for the patch includes checking for the following, during the removal process:

1) Is a chemical odor observed?

2) Are any holes observed in the film, when held to the light?

3) Is any redness observed under the pad?

4) Is the pad discolored? 

How long can the patch be worn

The skin has approximately 15 to 20 layers of skin cells. The top layer of cells is constantly being shed. How long a person can wear a PharmChek® Sweat Patch is determined by how long it takes for enough skin cells to be shed that the adhesive coating is completely covered with skin cells and can no longer stick to the subject’s body.

This length of time varies from person-to-person and skin type to skin type. From our wear tests we have determined that most people can wear the patch for 7 to 10 days. The Michigan Pilot Study showed 87% of the clients who wore the patch could wear it for 14 days. There are no known health concerns associated with wearing the PharmChek® Sweat Patch for periods longer than 14 days, provided the skin around and under the PharmChek® patch appears healthy and blemish-free.

What is considered a violation, and what happens after

A violation occurs when a candidate breaches a condition ordered by court or other agency. As it relates to Drug of Abuse monitoring it is considered when a test is failed or positive for controlled substances, you miss your reporting date; or if the patch is tampered with in any way. Any violation that occurs will be reported immediately to one or more of the following appropriate agencies: the prosecuting attorneys, court, LEO, or other agency. 

***The PSA may not only report violations, but also any progress and completion of program outlines. 

We would like to answer any questions you may have.

1 (307) 288-0247