Testing information
Prescribed stimulants and hair drug testing
If you take Vyvanse, dexamphetamine or another prescribed stimulant, declaring it at collection is the single thing that most affects how your report is read.
- Declare at collection
- Confirmed by mass spectrometry
- Results in 5–7 business days
Declare it before the sample is taken
Tell the collector about your prescription at the appointment, before the hair is cut. Declaring a lawful prescription up front is ordinary and expected. It is not an admission of anything, and it is what lets a positive amphetamine finding be read in context rather than left open to argument.
Explaining a result afterwards is a weaker position than declaring it beforehand, and it is the same information either way.
What to bring
- Your current prescription, or a repeat, showing the medication and the dose
- The prescribing doctor's name and clinic
- Anything else you take regularly, prescribed or over the counter
A photograph of the script on your phone is fine. Nothing is kept beyond what the chain of custody requires — see our privacy policy.
Screening and confirmation are two different tests
Most stories about a prescription causing a "false positive" come from a screening test. Screens are built to be fast and broad, so they group substances of a similar shape together. Confirmation is a separate analysis by mass spectrometry, and it names the compound rather than reacting to its outline.
What it measures
Screen
Whether anything in the amphetamine class is present
Confirmation
The exact compound, by its molecular signature
How specific it is
Screen
Reacts to molecules of a similar shape, so related substances register together
Confirmation
Identifies and quantifies each substance separately
What a positive means on its own
Screen
Something in the class is present. Which substance is still open
Confirmation
A named substance, at a measured concentration
Where it is used
Screen
Roadside swabs, workplace point-of-collection kits, initial urine screens
Confirmation
Every hair result reported by an independent NATA-accredited laboratory in Australia
| Screening testPresumptive | ConfirmationLC-MS/MS and GC-MS | |
|---|---|---|
| What it measures | Whether anything in the amphetamine class is present | The exact compound, by its molecular signature |
| How specific it is | Reacts to molecules of a similar shape, so related substances register together | Identifies and quantifies each substance separately |
| What a positive means on its own | Something in the class is present. Which substance is still open | A named substance, at a measured concentration |
| Where it is used | Roadside swabs, workplace point-of-collection kits, initial urine screens | Every hair result reported by an independent NATA-accredited laboratory in Australia |
Every hair result reported here has been through confirmation. The laboratory reports a drug at or above its cut-off, which for the amphetamine group is 20 pg/mg. That figure is the point at which a detection is reported at all, and it sits well below the low, medium and high bands on our hair test levels chart — so a result can be reported and still fall inside the band that means infrequent or incidental. The two numbers answer different questions and are worth keeping apart.
What confirmation can separate, and what it cannot
A methylamphetamine result cannot be explained by a prescription
Methylamphetamine — ice — breaks down partly into amphetamine in the body. The metabolism only runs that way. Dexamphetamine does not become methylamphetamine, so a methylamphetamine finding is not something a stimulant prescription accounts for.
Prescribed dexamphetamine and illicit amphetamine are the same substance
Dexamphetamine and amphetamine are two names for the same compound, and Vyvanse metabolises into it. No laboratory can tell a prescribed tablet from an illicitly obtained one, because there is nothing chemically different to find. What gives that result its meaning is the declared prescription, the dose, and the pattern across the whole report.
Reading the amphetamine and methylamphetamine figures together is what narrows it down, and it is worth understanding before anyone draws a conclusion from one line. We set out the three patterns and what each indicates in understanding methylamphetamine and amphetamine results.
What was found is exact. When it happened is an estimate.
Which substances are in the hair, and how much of each, is measured to a very high degree of certainty. The laboratory uses mass spectrometry, which identifies a molecule by its mass rather than inferring it from a colour change or a reaction. A positive result is a positive result.
Dating that use is the approximate part. Hair does not all grow at the same speed — individual follicles grow at slightly different rates, and some are resting at any given time. It is the same reason a haircut never grows out perfectly evenly. So a length of hair corresponds to an approximate period, not to a particular day.
These are two separate questions, and this is the part worth being clear about: an estimated timeline does not make the substance finding any less reliable. The chemistry is precise. The calendar is approximate.
Common questions
Should I stop my medication before the test?
No. Never stop or change a prescribed medication because of a test. That decision belongs with the doctor who prescribed it, and a gap in treatment does not improve a report — hair covers months, so recent changes affect very little of what is measured.
Will my ADHD prescription be held against me?
We collect the sample and an independent NATA-accredited laboratory in Australia analyses it. We do not decide what a result means for your matter, and we cannot tell you in advance how a court or an employer will weigh a declared prescription. What we can say is that a declared prescription is on the record from the start, which is the position you want to be in.
The other party says my result proves illicit use
That is what independent interpretation is for. Dr Robertson can review the report and give a written opinion a court, a solicitor or an employer can use, setting out what the analysis does and does not establish.
He interprets hair, blood, urine, saliva and breath results, including results produced by another laboratory, so an existing report can be sent to him. Request an interpretation.
Can you tell me whether my number looks like prescribed use?
No, and nobody should over a phone call or a chat window. That judgement needs the full report, the declared medication, the dose and the collection details in front of a forensic toxicologist. A general practitioner is not the person for it either — interpreting a forensic toxicology report is a different discipline.
For what the units mean and how the bands work, see what your results mean.
What about other prescribed medications?
The same principle applies to anything you are prescribed: declare it at collection. For medicinal cannabis specifically, we cover how a lawful prescription sits alongside a positive THC result in prescribed medicinal cannabis and drug testing.
Book a hair drug test
Same-day appointments are usually available at our Melbourne clinic, and results are back within 5–7 business days.