UNDERSTANDING THC AND DUI TESTS FOR MEDICINAL CANNABIS PATIENTS
- Teresita "Angela" Terga
- Sep 17
- 9 min read
Updated: Sep 19
As seniors, many of us know the daily struggle of living with chronic pain, arthritis, or conditions that make every movement harder than it used to be. While prescription narcotics and invasive medical treatments are often offered, they can leave us with side effects we’d rather avoid. That’s why more older adults are looking toward natural, holistic remedies like medicinal cannabis, which has become an increasingly respected option in today’s wellness industry. But with this choice comes an important question: how does using marijuana affect our ability to drive, and what do DUI tests really measure when it comes to THC?
This Blog Post shares the insights in the link below, in case you need to consult an attorney further about the legal options you might have.
We are sharing this blog post from NSTLAW.COM on TAT Productions' The Blog of Angela Terga—"Memoirs of a Mad Teacher," which is also accessible through our foundation, CAMP—camp1.org, a non-profit organization dedicated to supporting artists across all disciplines in achieving their dreams. Our goal is to provide you with a clear understanding of DUI laws and encourage you to take the necessary precautions to avoid a DUI charge. Whether you use THC for medicinal purposes or know someone who does, please share this information.
In my roles as a teacher, mother, friend, senior, and media caster, I am responsible for raising awareness and helping to prevent situations that harm the well-being of those involved. Many adults and teenagers use THC products not just to experience a high. While THC might offer a glimpse of bliss, it ultimately turns users into insatiable seekers. The burden is heavy for families and individuals trapped in the chains of addiction.
Although THC is often seen as having various beneficial effects, making it a favored medicinal choice for tackling issues such as pharmaceutical drug dependency, arthritis, acute pain, and even depression, there are also multiple warnings and contraindications linked to its use.
Keep in mind that love is the ultimate remedy for everything. If you're facing a situation, discuss it with a friend or pastor. Acknowledge it. Strive to enhance your relationships and achieve inner peace. Engage CAMP to bring the gift of conscious arts into your life, at no cost.
Marijuana is a double-edged sword. Be cautious of its adverse effects and the legal consequences that 'driving under the influence' can impose on you and society.
Marijuana and Driving: Understanding THC Impairment and DUI TESTS
With the expansion of marijuana legalization, the issue of driving under the influence of cannabis has gained urgency. Unlike alcohol, where blood alcohol concentration (BAC) serves as a clear indicator of impairment, THC levels in the body are much more unpredictable. Researchers and law enforcement are exploring various methods, such as THC breath tests and field sobriety tests for marijuana, to find dependable ways to assess impairment on the road.
This guide examines the difficulties in detecting cannabis DUI, the recommended waiting period before driving after using marijuana, and insights from current and new tests regarding cannabis impairment.
Why Marijuana Impairment Is Harder to Measure Than Alcohol
With alcohol, predicting impairment is quite straightforward: BAC levels increase and decrease in predictable patterns, and beverage bottles clearly display alcohol content. Marijuana, however, is different. THC potency can vary greatly depending on the product, method of use, and how often it is used.
Daily cannabis users may still test positive for THC more than 12 hours after use (Traffic Injury Prevention).
Blood tests—the current standard—don’t always reflect actual impairment, since THC lingers in the body long after its effects fade.
THC is chemically unstable, making results unreliable if blood samples aren’t handled or stored correctly.
The shift toward THC breath tests using nanotechnology promised The move toward THC breath tests with nanotechnology promised progress, but because THC stays detectable for so long, these tests still have trouble measuring real-time impairment.progress, but because THC remains detectable for so long, these tests still struggle to determine real-time impairment.
Field Sobriety Tests for Marijuana: Traditional Methods
Given the drawbacks of chemical testing, law enforcement continues to use field sobriety tests (FSTs) as part of cannabis DUI assessments. Given the limitations of chemical testing, law enforcement still uses field sobriety tests (FSTs) as part of cannabis DUI evaluations. These physical and mental assessments check coordination, balance, and focus, providing clues about impairment.These physical and cognitive tests measure coordination, balance, and focus, offering clues about impairment.
Common sobriety tests include:
Horizontal Gaze Nystagmus – Detects involuntary eye movement, though it’s reliable mainly for alcohol.
One Leg Stand – Challenges balance and reveals motor control issues linked to heavy drug use.
Modified Romberg Balance – Tests balance, time perception, and coordination.
Walk and Turn – The classic straight-line walking test assessing attention and focus.
While field sobriety tests for cannabis aren’t perfect, they can provide valuable insights when combined with blood or breath tests, creating a fuller picture of driver impairment.
Neurocognitive Tests: The Next Generation of Cannabis DUI Detection
Technology is expanding the definition of sobriety testing. Neurocognitive assessments go beyond physical coordination to measure reaction time, hand-eye coordination, and executive function—all areas marijuana can impair.
Two emerging tools stand out:
DRUID App (Driving Under the Influence of Drugs) – A mobile tool developed in Massachusetts that tests hand-eye coordination. Initially designed for personal self-checks, it could become a law enforcement resource.
AlertMeter – Originally created for workplace safety, this test distinguishes between residual THC in the body and genuine impairment, making it promising for marijuana impairment detection in drivers.
These digital tools could eventually complement traditional marijuana DUI tests, balancing accuracy with fairness.
How Long Should You Wait to Drive After Using Marijuana?
No universal national guideline exists, but the Colorado Department of Public Health and Environment recommends:
Wait at least six hours after smoking less than 35 mg of THC.
Wait at least eight hours after eating or drinking less than 18 mg of THC.
For context:
A typical marijuana cigarette contains about 60 mg of THC.
Edibles usually have 10 mg per serving.
Because the “high” and subsequent drowsiness often last much longer, experts advise waiting at least 12 hours before driving after marijuana use.
Driving High vs. Driving Drunk
Both alcohol and marijuana impair driving, but in different ways:
Alcohol often leads to reckless, aggressive driving.
Marijuana slows reaction times and reduces coordination.
Combining alcohol and cannabis significantly increases crash risk.
In short, neither is safe—driving high is dangerous, and driving drunk is no better.
Current and Future Marijuana DUI Testing Methods
Right now, marijuana DUI laws rely on a mix of tools, each with limitations:
Blood tests – Measure THC levels, but don’t always reflect real impairment.
Breath tests – Detect THC presence, but can’t reliably gauge intoxication.
Field sobriety tests – Provide observational insights but can be subjective.
Neurocognitive tools – A promising frontier that targets mental performance.
The most accurate cannabis impairment detection will likely come from combining these methods rather than relying on any single test.
Marijuana and Driving: Quick Quiz
1. How long should you wait to drive after smoking less than 35 mg of THC?
A) 2 hours
B) 4 hours
C) 6 hours
D) 12 hours
✅ Answer: C – 6 hours (though 12 hours is safer).
2. How long should you wait to drive after eating less than 18 mg of THC?
A) 4 hours
B) 6 hours
C) 8 hours
D) 10 hours
✅ Answer: C – 8 hours.
3. A typical marijuana cigarette contains about how much THC?
A) 10 mg
B) 35 mg
C) 60 mg
D) 100 mg
✅ Answer: C – 60 mg.
4. Can you drive safely while high?
A) Yes, marijuana doesn’t impair driving.
B) Sometimes, depending on the dose.
C) No, marijuana slows reaction time and coordination.
D) Only if combined with alcohol.
✅ Answer: C – No, marijuana impairs judgment, reaction time, and coordination.
5. Is it worse to drive high or drive drunk?
A) Driving drunk
B) Driving high
C) Both impair driving in different ways
D) Neither affects driving
✅ Answer: C – Both impair driving in different ways, and both increase crash risk.
6. How is marijuana intoxication currently determined?
A) Blood and breath tests
B) Field sobriety tests
C) Neurocognitive tools like apps
D) All of the above
✅ Answer: D – All of the above, though none are perfectly reliable.
Final Takeaway
With marijuana legalization expanding, cannabis DUI laws and THC impairment testing are evolving rapidly. The science is still catching up, but one principle remains clear: if you’re high, don’t drive. Waiting the recommended time—or longer—is the only way to ensure safety for yourself and others on the road.
When it comes to driving under the influence, alcohol and marijuana are not measured on equal ground. For alcohol, the science is relatively straightforward. Blood alcohol concentration (BAC) levels correlate directly with impairment, and beverage containers clearly list alcohol volumes. With marijuana, however, the picture is much more complicated.
The Challenge of Measuring THC
Unlike alcohol, THC potency varies dramatically depending on the cannabis product and how much is consumed. Even more challenging, frequency of use has a major impact on how long THC lingers in the body.
For example, a study published in Traffic Injury Prevention found that daily cannabis users still tested positive for THC even after abstaining for more than 12 hours. This makes it nearly impossible to create a “universal safe waiting period” for marijuana use the way we can for alcohol.
The Limitations of Blood Testing
Currently, blood tests are the standard method for detecting THC. But these tests don’t necessarily reflect impairment. A person might test positive for THC yet show no functional impairment, while another person might be impaired with relatively low THC levels.
On top of that, THC is chemically unstable. If blood samples aren’t stored properly or analyzed within three months, THC levels can degrade, leading to underestimated results. This undermines the reliability of the very tests law enforcement depends on.
The Rise of THC Breath Tests
In an effort to improve testing, researchers are developing breath-based THC detection using nanotechnology. These devices promise faster results, but they face the same fundamental challenge: THC can remain in the body long after impairment has worn off. Just like blood tests, a breath test may detect the presence of THC without accurately measuring intoxication.
The Road Ahead
As marijuana legalization expands, law enforcement faces increasing pressure to find fair and accurate ways of determining impairment on the road. For now, however, the science remains inconclusive. Unlike alcohol, THC doesn’t follow a clear timeline in the body, making it a complex substance to regulate when it comes to safe driving.
Until testing methods catch up with reality, the best advice for cannabis users is simple: if you’ve consumed, don’t drive.
Having understood the risks associated with driving under the influence of cannabis, here is a step-by-step guide to begin your path to safe cannabis use if you are experiencing:
Chronic Pain, Stress, PTSD, Insomnia, or any other Qualifying ConditioN?
To start your journey as a screened, licensed, and prescription cannabis consumer, here’s a clear list of the most common qualifying conditions for medical cannabis based on Florida law. Dr. Masse at WellingtonCBD.com will let you know if your condition qualifies.
Florida Medical Cannabis Qualifying Conditions
Cancer
Epilepsy
Glaucoma
HIV/AIDS
Post-Traumatic Stress Disorder (PTSD)
Amyotrophic Lateral Sclerosis (ALS)
Crohn’s Disease
Parkinson’s Disease
Multiple Sclerosis (MS)
Chronic Nonmalignant Pain (lasting more than 3 months)
Medical conditions of the same kind or class as those listed (doctor’s discretion)
Terminal illness (diagnosed by a physician other than the qualifying doctor)
Other debilitating conditions comparable to the above, as determined by a qualified physician
In Florida, physicians like Dr. Masse can also recommend medical cannabis for conditions “of the same kind or class” or for other serious, chronic health issues where traditional treatments have not worked.
Step 1:
Schedule Your Doctor’s Appointment
The first step toward obtaining your medical cannabis license is to book an appointment with a qualified physician such as Dr. Masse at WellingtonCBD.com. During this visit, the doctor will review your medical history, discuss your current health concerns, and determine whether you meet the state’s eligibility requirements for medical cannabis. Be sure to bring any relevant records and a valid photo ID.
Step 2:
Receive Your Physician’s Recommendation
If the doctor confirms that medical cannabis could benefit your condition, they will enter your information into the state’s Medical Marijuana Use Registry. This official recommendation is necessary for moving forward. The process is straightforward and typically completed during your appointment. Once registered, you will receive login credentials from the state system to manage your application.
Step 3:
Apply for Your License and Fill Your Prescription
After the physician’s recommendation, you can submit your application to the state online or by mail, including proof of residency and the required fee. Approval generally takes a few weeks. Once you receive your Medical Marijuana Use ID card, you can fill your prescription at licensed dispensaries. From there, you and your doctor can adjust your treatment plan as needed for safe, effective relief.
In Florida, after a qualified physician like Dr. Masse enters your recommendation into the Medical Marijuana Use Registry (MMUR), patients must submit their application directly to the Florida Office of Medical Marijuana Use (OMMU).
Applications can be completed online through the MMUR portal or by mail.
You’ll need to provide:
Proof of Florida residency (driver’s license or state ID for permanent residents, alternative docs for seasonal residents).
A passport-style photo (usually auto-pulled if you have a Florida ID).
The state application fee ($75).
Once approved, you’ll receive your Medical Marijuana Use ID Card by mail, which allows you to purchase cannabis products from licensed Florida dispensaries.
⏱️ Processing time: Typically 2–3 weeks after submission.
🌿 Looking for compassionate care and expert guidance on medical cannabis?
From your initial consultation to your state application and medical cannabis card approval, Dr. Masse makes the process simple and stress-free. Patients trust his experience, professionalism, and dedication to holistic health.
📋 To Book your appointment and take the first step toward safe, effective relief and responsible use:
👉 Visit WellingtonCBD.com or call to schedule.
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