“Blood Tests” after Nevada DUI Arrests (2026 Updates)

In Nevada, a driver arrested for an alcohol-related DUI can generally choose between taking an evidentiary (“chemical”) blood test or a breath test. Driving with a blood alcohol concentration (BAC) of 0.08% or higher is “per se” unlawful.

If police suspect drug use, they may require a blood test, a urine test, or both. If the driver refuses a required test, police may ask a judge for a warrant or court order allowing a forced blood draw.

When Police Use Blood Tests

• Alcohol-related DUI:  When alcohol concentration is the issue, you may usually choose between an evidentiary breath test and a blood test.
• Drugged driving:  If police suspect drugs (including marijuana), they may require a blood test, a urine test, or both.
• Unconscious driver:  Nevada law directs the officer to have blood samples taken when the DUI suspect is unconscious.
• Failed or refused testing:  If you refuse a required chemical test, officers may seek a warrant authorizing a blood draw with reasonable force.
• Medical exemption:  A person with hemophilia or a physician-confirmed heart condition requiring anticoagulants is exempt from a required blood test but may have to take a breath or urine test.

Blood Tests and Your Driver’s License

• Delayed results:  If you consent to a blood test, you can usually keep your license while waiting for the results.
• Refusal revocation:  Refusing a required chemical test triggers an immediate confiscation of your license and a revocation for one year (or for three years if you have a prior refusal in the last seven years).
• Separate proceedings:  The DMV case and the criminal DUI case are separate matters. You have to win both in order to avoid a license revocation.

Challenging Blood Tests

A Nevada DUI lawyer can examine:

• Whether the traffic stop and arrest were lawful;
• Whether a warrant was required and supported by probable cause;
• Who drew the blood and whether proper procedures were followed;
• Whether the vial contained the correct preservatives and anticoagulants;
• Whether the sample was contaminated, fermented, coagulated, or improperly stored;
• Whether every transfer of the sample was documented;
• Whether the laboratory equipment and testing method were reliable; and
• Whether an independent retest produces a different result.

Unlike a breath test, a blood draw leaves a physical sample that we can usually have independently analyzed. In our experience, that makes it especially important to obtain the laboratory records, chain-of-custody documents, and remaining sample before evidence becomes harder to locate. If we can show the D.A. there is reasonable doubt as to your blood test’s accuracy, your entire case could be dismissed.

In this article, our Las Vegas drunk driving attorneys will address the following key issues regarding Nevada DUI blood tests:

• 1. When Blood Tests Are Used
• 2. Driver’s License Consequences
• 3. Failing Results
• 4. Passing Results
• 5. Refusals
• 6. Time Limits
• 7. Independent Testing
• 8. Costs
• 9. Challenging the Results
• 10. Blood vs. Breath
• 11. Urine Tests
• Frequently Asked Questions
• Additional Reading

1. When Blood Tests Are Used

If Nevada police arrest you for “drugged driving,” they may require a blood test, a urine test, or both. This is because breath tests detect alcohol but not drugs.

If you are suspected of “drunk driving,” you can elect to take either:

• an evidentiary breath test or
• a blood test.

However, if you are unconscious (such as after a car accident), the arresting officer will order that a blood sample be taken.

If you are on anticoagulants or have hemophilia, you are exempt from taking evidentiary blood tests. Instead, the police can order you to take a breath test or a urine test if a breath test is unavailable or drugs are suspected.¹

2. Driver’s License Consequences

If you consent to take a blood test following a Nevada DUI arrest, you can usually keep your license while waiting for the results. If the result is 0.08% or higher, the Nevada Department of Motor Vehicles will mail you a notice of revocation.

You then have seven days to request a DMV hearing to contest the license revocation. Meanwhile, you can continue driving pending the results of the DMV hearing, which may be another month or two away. Your defense attorney can appear at this hearing on your behalf.

Note that the DMV hearing is an administrative proceeding that is completely separate from the criminal case. You can win the DMV hearing and lose the criminal case, and vice versa. The only way to avoid a license revocation is to win both the DMV hearing and the criminal case.²

3. Failing Results

Nevada law prohibits driving with a blood alcohol concentration (BAC) of 0.08% or higher. Even if you were driving safely and seemed sober, you can still be convicted under Nevada’s per se DUI law.

Note that drivers under 21 are held to a stricter standard: They face a 90-day driver’s license suspension for a BAC of 0.02% to less than 0.08%. (Learn more about underage DUI.)

As the following table shows, Nevada law also makes it “per se” illegal to drive with certain blood levels of various drugs:

Drug	Unlawful Blood Levels while Driving in Nevada
Amphetamine	100 ng/mL
Cocaine	50 ng/mL
Cocaine metabolite	50 ng/mL
Heroin	50 ng/mL
Heroin metabolite:  Morphine	50 ng/mL
Heroin metabolite:  6-monoacetyl morphine	10 ng/mL
Lysergic acid diethylamide	10 ng/mL
Marijuana (only for third- or successive DUIs in a seven-year period)	2 ng/mL
Marijuana metabolite (only for third- or successive DUIs in a seven-year period)	5 ng/mL
Methamphetamine (Meth)	100 ng/mL
Phencyclidine	10 ng/mL

Nevada DUI law does not establish a specific “per se” lawful limit for many common prescription medications, such as Xanax (alprazolam) or Ambien (zolpidem). There is also no “per se” DUI limit for marijuana in first-time or second-time DUI cases.

In such “drugged driving” cases where there is no “per se” lawful limit, simply having these drugs in your system is not automatically a crime. To convict you, the prosecutor must prove beyond a reasonable doubt that the drugs in your blood actually impaired your ability to drive safely. So in addition to blood test results, prosecutors would likely introduce evidence regarding driving behavior, physical symptoms, field observations, or other evidence of impaired driving.³

4. Passing Results

A BAC below 0.08% does not always prevent a Nevada DUI conviction. Prosecutors may still try to prove that alcohol, drugs, or a combination of substances made you unable to drive safely.⁴ However, a result below the applicable per se limit removes one theory of the case and may make DUI harder to prove.

5. Refusals

If you refuse a required evidentiary breath or blood test following a Nevada DUI arrest, police will confiscate your driver’s license and may apply for a warrant or court order to obtain a blood sample.

Then, once the warrant or court order is issued, police can use necessary “reasonable force” on you to carry out a forced blood draw. The only time police can make a warrantless blood draw without your consent is if a true exigency exists that makes it impracticable to get a warrant.⁵

In addition, refusing to submit to a blood test when required carries a one-year license revocation – even if the DUI charges get dropped.⁶ The revocation increases to three years if your license was revoked for another test refusal during the last seven years.⁷

If your DUI case goes to trial, the prosecution can admit evidence that you refused the test.⁸

A warrant does not automatically make a blood draw lawful. We can examine whether the warrant application established probable cause, accurately described the evidence known to police, and authorized the draw that was actually performed. If it turns out the warrant was materially defective, we can ask the court to suppress the blood draw results as evidence.

6. Time Limits

It is DUI per se in Nevada if your BAC or applicable drug level was unlawful while you were driving or within two hours after you stopped driving. A sample collected later than two hours is not automatically excluded, but prosecutors may need an expert or other evidence to connect the result to the relevant time.

Nevada police generally may obtain no more than three blood or breath samples during the five hours immediately after the initial arrest.⁹

7. Independent Testing

In Nevada, you can have your DUI blood samples independently tested. This is sometimes called a “blood split.”

We highly recommend blood splits. An independent test may show that the result reported by law enforcement was inaccurate or that the sample was mishandled.

8. Costs

If you request a blood test when an evidentiary breath test is reasonably available and you are later convicted, the court may require you to pay the blood test costs. These costs vary widely depending on the lab.

Costs may also include fees and expenses for witnesses needed at the criminal trial or DMV hearing. Witnesses cost at least:

• $100 an hour plus
• $50 an hour for traveling.¹⁰

9. Challenging the Results

Nevada has rules for collecting, storing, and testing DUI blood samples. A mistake may weaken the result or, in some cases, keep it out of evidence. This can lead to a reduced charge or dismissal, depending on the rest of the case.

The following are just seven defenses we may use to challenge the validity of Nevada DUI blood test results:

1. The blood testing equipment was either broken, not properly maintained, or otherwise faulty.
2. The phlebotomist, registered nurse, or technician who administered or tested the blood was not properly certified.
3. The blood test was taken too long after the initial arrest to determine whether you were under the influence.
4. There was a break in the blood sample’s chain of custody, so the sample may have been switched or contaminated.
5. The blood fermented after collection, which means it can create its own alcohol and yield falsely high results.
6. The phlebotomist sterilized the blood draw site with an alcohol-based product, which could have caused an inaccurately high BAC reading.
7. The blood was stored improperly, or there were inadequate levels of anticoagulants and preservatives in the vial.

We would obtain more than the final laboratory number. We would also review the blood draw report, warrant papers, chain-of-custody logs, vial lot and expiration information, equipment maintenance records, quality control data, chromatograms, and the analyst’s notes.

Blood vials ordinarily contain preservatives intended to limit fermentation and anticoagulants intended to prevent clotting. An expired vial, an incorrect chemical concentration, inadequate mixing, contamination, or coagulation can undermine the reliability of the reported result. A forensic toxicologist may be able to identify problems that are not apparent from the reported BAC or drug concentration alone.

We would also gather information regarding your medical conditions, medications, alcohol or food consumed near the time of driving, the timing of the last drink, and anything unusual about the blood draw. Medical records, body camera footage, dispatch records, and laboratory documents may contain information that undercuts the state’s case.

Ultimately, if we can show prosecutors that the state’s evidence is too weak to prevail at trial, prosecutors may agree to reduce the criminal charges or even dismiss the case outright.

What about the “Rising Blood Alcohol” defense?

Because alcohol takes time to fully absorb into the bloodstream, your BAC can continue to climb long after you stop drinking. The “rising blood alcohol” defense argues that a driver’s BAC was completely legal while they were behind the wheel, but rose to an illegal level by the time police administered a breath or blood test.

While scientifically accurate, the rising blood alcohol defense is generally ineffective since Nevada law defines a DUI as having a BAC of 0.08% or higher within two hours of driving. Consequently, even if your BAC was under the legal limit at the exact moment you were driving, you can still be convicted if your body absorbs enough alcohol to hit 0.08% within the two hours following your traffic stop.

If police test you more than two hours after you stopped driving, the result is not automatically excluded. However, we may argue that the later result does not prove your BAC was 0.08% or higher during the two-hour period covered by Nevada’s per se law.

10. Blood vs. Breath

The following chart compares breath tests and blood tests in Nevada DUI cases:

NEVADA LAW	DUI Blood Tests	DUI Breath Tests
Accuracy	Generally more accurate	Less accurate, can be affected by acid reflux, GERD, mouth alcohol, and more
Invasiveness	Invasive, requires blood draw	Non-invasive, requires breathing into a device
Time to results	Longer, typically weeks	Immediate results
Administration	Requires medical professional	Can be administered by law enforcement
How it measures alcohol	Direct measurement of blood alcohol concentration (BAC)	Estimates BAC based on breath alcohol content
Detects drugs?	Yes	No
Retention of sample	Sample can be retained for future testing	No sample retention
Refusal consequences	Driver’s license revocation	Driver’s license revocation

11. Urine Tests

There are circumstances where you may be unable to provide a blood sample following a DUI arrest in Nevada. Examples are:

• The police have no phlebotomist on hand,
• You are on anticoagulants (such as for blood clotting conditions), or
• You have hemophilia.

If a blood test is not feasible, police may use a breath or urine test when allowed by law. If drugs are suspected, police may request blood, urine, or both.

Urine tests are not as accurate as breath or blood tests and may give false positives. Urine tests can also detect alcohol that was consumed a full 24 hours earlier and therefore had zero impact on your recent driving.

If you do take a urine test in your DUI case, your attorney may be able to contest the result in court.¹¹

Frequently Asked Questions

What happens to my driver’s license if I take a blood test after a DUI arrest?

If you take a blood test and did not separately refuse another required test, you can usually keep your license while waiting for the results. If your BAC is 0.08% or higher, the DMV will mail you a revocation notice. You then have seven days to request a DMV hearing to contest the revocation, and you can generally continue driving while waiting for the hearing.

Do I have to take a blood test for a DUI in Nevada?

If alcohol is the issue, you generally may choose between a breath test and a blood test. If police suspect drugs, they may require blood, urine, or both. Nevada law also directs officers to obtain blood samples from an unconscious driver.

What happens if I refuse a DUI blood test in Nevada?

Under Nevada’s implied consent laws, refusing a chemical test results in an automatic one-year revocation of your driver’s license, even if your criminal DUI charges are eventually dropped. Furthermore, police can apply for a warrant to physically force a blood draw. (If you have a prior refusal in the last seven years, the license revocation period is three years.)

Can police force me to take a blood test if I refuse?

Yes, potentially. If you refuse a required test, police may apply for a warrant or court order allowing a blood draw with reasonable force. This is why it is usually better just to consent to the test upfront.

How long after my arrest can police take my blood for DUI testing?

Police generally may obtain no more than three blood or breath samples during the five hours after the initial arrest. A blood sample taken more than two hours after driving is not automatically excluded. However, its timing may make it harder for prosecutors to prove that your BAC or drug level was unlawful during the two-hour period covered by Nevada’s per se DUI law.

What drug levels in my blood are illegal for driving in Nevada?

Nevada has specific illegal blood levels for various drugs, such as 100 ng/mL for amphetamine and meth, 50 ng/mL for cocaine and heroin, and 10 ng/mL for PCP and LSD. For marijuana, the limit is 2 ng/mL, but only for third or repeat DUI offenses. For prescription drugs like Xanax, there’s no set limit – prosecutors must prove the drugs actually impaired your driving.

Can a Nevada DUI blood test be wrong?

Yes. Blood tests can yield falsely high results or be completely invalidated due to human error. Common defenses include challenging the results because the blood fermented, the sample was contaminated, the chain of custody was broken, or the person who drew the blood was not properly certified.

Who pays for the DUI blood test in Nevada?

If you requested a blood test when a breath test was reasonably available and you are later convicted, the court may require you to pay the blood test costs. This may include certain fees and expenses for witnesses needed at your trial or DMV hearing.

What is the legal limit for marijuana in a Nevada DUI blood test?

For an ordinary first or second DUI, Nevada has no per se marijuana limit, so prosecutors generally must prove that THC impaired your driving. The limits of 2 ng/mL of marijuana and 5 ng/mL of marijuana metabolite apply in the repeat-offender cases listed in NRS 484C.110(4), including when the driver has two qualifying prior DUI offenses within seven years or a qualifying prior felony DUI conviction.

Learn more about DUI of marijuana.

Additional Reading

For more in-depth information, refer to these scholarly articles:

• Delays in DUI blood testing: Impact on cannabis DUI assessments – Traffic Injury Prevention.
• Variability of the Blood/Breath Alcohol Ratio in Drinking Drivers – ASTM Journal of Forensic Sciences.
• Breath and Blood Alcohol Concentration Measurement in DUI Cases – Forensic Metrology.
• Drunk Driving, Blood, and Breath: The Impact of Birchfield v. North Dakota – Cornell Journal of Law & Public Policy.

See our related articles, Can police do a forced blood draw in a Nevada DUI arrest?, field sobriety tests and sealing criminal records for DUI offenses.

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Legal References