Prescription Drug DUI

PRESCRIPTION DRUG DUI

Impairment Due to Medication Not Taken "As Prescribed"

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Your Legal Professionals for Prescription Drug DUI in Phoenix, Arizona

DRUG DUI Lawyer IN PHOENIX, AZ- KOPLOW LAW FIRM
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Prescription Drug DUI in Arizona results from driving with a drug in your system while, either:

(1) being impaired

(2) without a prescription

(3) not using as prescribed

Arizona PRESCRIPTION DRUG DUI | MEDICATION DUI
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“But I had a prescription!”

Obviously it’s illegal to drive impaired by Oxycotine…even if you have a prescription. The same is true with marijuana or any other drug. However, how would the police determine if you were impaired by a prescription drug?

No Universal Level of Impairment



It is generally accepted in the scientific community, that at an alcohol concentration of .08, just about everyone is impaired for the task of driving. However, the same is not true for drugs. Neuropharmacology has shown significant differences in the way alcohol and other drugs affect the body.


There is no such correlation for the amount of a drug in your blood (or urine) and impairment. The result of a chemical test is simply not capable of proving impairment.

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“CAVEAT INTERPRETOR! As man does not live only by bread, so the toxicologist cannot interpret his results by numbers alone...”

Dr. Irving Sunshine, World-Renown Toxicologist

But What About the Therapeutic Range?

The government often argues that a therapeutic level is evidence of drug impairment. They do this by reference to a drug’s therapeutic level.

A drug’s therapeutic level refers to either: (1) The dosage range or (1) Blood plasma / serum concentration usually expected to achieve desired therapeutic effects.

Arizona DUI Prescription Drug DUI Blood Therapeutic Range

In more basic terms, the purpose of most psychiatric medications is get the person to her “normal” state of being. That is a valid and desired medical purpose.

Panic Attacks

Think about the person who suffers from panic attacks. Is it safer for that person to drive properly medicated (and unimpaired) with their medication or without? I would prefer properly medicated.


When medication is achieving it’s desired result we know the person has the proper amount. At this point, the level of the drug in a person’s system is the therapeutic level. This level for any particular drug will vary from person to person. Contrary to how it is often presented by the prosecution, it is not evidence of impairment.

"As Prescribed"

If you took Valium the day before drove to work then the effects have long subsided. While driving to work the next you no longer impaired by this drug. Keep in mind, the reason you were prescribed the medication was an anxiety condition. So when the officer stopped you for speeding it was predictable that your condition was triggered by traffic stop by law enforcement. The symptoms you’re exhibiting could easily be mistaken for impairment.

Arizona Prescription Drug DUI | Medication DUI | Arizona Questions

Now that the officer arrested you for DUI, mistakenly believing your were impaired by the medication, you have a defense. Assuming you can prove that the symptoms impairment were not caused by a drug – then you have a legal defense that you had a valid prescription. Put another way, the law states it’s a defense to the allegation that there was a controlled substance in your system, if you have a valid prescription. 

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Arizona Prescription Drug DUI FAQS


  • How does Arizona define a prescription drug in a DUI case?

    A chemical test cannot determine if you are impaired by THCWe all understand that “prescription” drugs are the medications your doctor have determined you need to treat some medical condition and have given you permission you to use. This is commonly done by giving you a written prescription or by a direct call from the medical provider to your pharmacy. However, in the case of driving under the influence laws, Arizona has given some additional legal meaning what we commonly consider as prescription drugs.


    ARS 13-3401(28) provides that a “Prescription-only drug” does not include a dangerous drug or narcotic drug but means:


    (a) Any drug which because of its toxicity or other potentiality for harmful effect, or the method of its use, or the collateral measures necessary to its use, is not generally recognized among experts, qualified by scientific training and experience to evaluate its safety and efficacy, as safe for use except by or under the supervision of a medical practitioner.


    (b) Any drug that is limited by an approved new drug application under the federal act or section 32-1962 to use under the supervision of a medical practitioner.


    (c) Every potentially harmful drug, the labeling of which does not bear or contain full and adequate directions for use by the consumer.


    (d) Any drug required by the federal act to bear on its label the legend “


    Another way to think about this is, a drug will fall within this legal definition if, the medical community has recognized it is safe when taken as prescribed by a doctor.. The only thing a blood, urine or saliva test can do is show prior use of the drug. 

  • How to fight DUI charge for prescription drugs?

    Take a look at my ESSENTIAL GUIDE TO DEFENDING DRUG DUI CASES.

  • Can legal drug use turn into a DUI?

    Yes.  Consider the person who was legally given morphine at a hospital for an injury.  They then drive home from the hospital while still impaired by the medication.  This is a textbook example of a case that started with legal drug use and then turned into a DUI.

  • Is it illegal to drive on Percocet?

    See the question and answer above.

  • Does Arizona have a “minimum” level for prescription-drug impairment?

    No.  In the case of a DUI based upon the consumption of alcohol, Arizona has “per se” laws.  For example, it is illegal for a person to drive with an alcohol concentration of .08 (the makes a presumption that a person is impaired at this level).   This is not the case when it comes to a prescription drug DUI allegation.


    This actually makes a lot of sense as, unlike alcohol, there is no universal level of impairment when it comes to drugs.  The way prescription drugs affect the human body is very different than alcohol.  Simply put, when it comes to prescription medications, there is no numerical definition of chemical impairment.

  • What happens if I drive after taking someone else’s prescription medication?

    Driving with a prohibited drug in your system, in and of itself, is a violation of Arizona’s DUI laws.  This is technically true even if you are not impaired by the drug. 

  • Why did I get two charges after being arrested for a prescription drug DUI?

    Receiving two charges for prescription medication DUI is standard practice.


    One charge alleges you were impaired while driving. The other charge claims you have a drug in your system that was either illegal or you did not have valid prescription for its use.


    Receiving these two charges does not mean your case was worse than other Arizona prescription cases.  

  • What are the penalties for drugged driving in Arizona?

    A first offense DUI based upon prescription drug is a Class 1 misdemeanor and the penalties are the same as an alcohol DUI. 

  • Have you seen cases where someone took a sleep aid and was charged the next day with DUI?

    Yes, but these cases should not be charged by the government.  Drugs like Ambien sometimes have unintended consequences that were not the result of a voluntary act.


  • Is it more difficult for the government to convict a person of a prescription drug DUI?

    It can be the case.  There are a lot of discussions about this issue in the legal community.

  • Is it a defense if I accidentally took the wrong pill?

    While there is some debate on this issue, I believe it is a defense under Arizona law.

  • Xanax DUI?

    You can get a DUI on Xanax. Xanax is common medication found in driving while under the influence of drugs cases.

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"Lawrence represents very high-profile clients who greatly depend on a good outcome, and this guy will deliver. 

This is a prosecutor's worst nightmare, and it should be that way if you need an attorney."

- David E.

Real Client's Husband, Phoenix, AZ

Hiring an Experienced Prescription Drug DUI Attorney in Phoenix

Arizona DUI law is extremely complicated and has severe consequences. DUI law is commonly referred to as a minefield. An attorney must be competent in the Arizona Rules of “Criminal” Procedure, the Arizona Rules of Evidence, the United States and Arizona Constitutions, and the Arizona Department of Motor Vehicles Rules and Regulations.


An attorney cannot do anything for you unless he or she has extensive experience in these areas.  Police officers are only human and do commit legal errors.  However, only an experienced DUI attorney will be able to find these errors and use them to help his or her client.


You should choose an experienced DUI attorney for the same reason you should choose a qualified doctor. If you break your wrist, you go to a doctor that specializes in wrist injuries. When you are charged with a DUI, you should hire a qualified DUI attorney.


An experienced Arizona DUI attorney can analyze your case for legal errors and defenses. He or she can have blood samples independently analyzed, look for suppression issues, review calibration / COBRA records of breath machines, find the right expert witnesses for your trial, and assist you with your driver’s license issues.

For more information, call our office at (602) 494-3444 or visit our contact page.
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What Real People Are Saying

That is, DUI cases actually dismissed. Verifiable not guilty verdicts. Blood alcohol evidence truly suppressed as witnessed by judges, other lawyers, and newspapers.

Real Client's Husband, Phoenix, AZ

"Lawrence represents very high-profile clients who greatly depend on a good outcome, and this guy will deliver. 

This is a prosecutors' worse nightmare, and it should be that way if you need an attorney."

 - David E.

REAL CLIENT, PHOENIX, AZ

It was miracle!... A lot of people don't really understand the benefit of having an attorney who used to be a prosecutor. They know all the little tricks and scare tactics the state has as opposed to just hiring an attorney who is a little fish in a big pond."

 - Joe C.

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For more information, call our office at (602) 494-3444 or fill out the form and we will get back to you.

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