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Are There Established Therapeutic Levels for Prescription Medication?

Interviewer: Is there a therapeutic level that police test for when they test your blood or a threshold for these medications?

Brian: There are therapeutic levels, scientifically declared therapeutic levels. However, the problem is especially when we’re talking about count two, when someone is driving with medication in their system and they are taking it as prescribed.

When we have printed therapeutic levels, whether someone is inside those therapeutic levels or outside of those therapeutic levels that doesn’t necessarily speak to whether someone is taking the medication as prescribed. They are really two different things.

The law does not say that it is legal to drive within therapeutic levels. The law does not say that is a defense to count two DUI, if someone is driving on prescription medications and the prescription medication are being taken within therapeutic levels.

The law says that it is a defense if a person is taking prescription medications and they are taking those medications as prescribed. Therapeutic levels don’t really speak to that.

Therapeutic Levels Cannot Be Used in a Defense  

For example, someone who has been taking medications for years tend to have a build-up of those prescription medications and as time goes on, there is a lessening effect that those prescription medications have on them, so they need to take higher dosages.

If the person has been on the medication for a long time they may show that outside of normal therapeutic levels but they are literally taking the medication as prescribed.

The prosecutor can talk about therapeutic levels, the defense can talk about therapeutic levels, and in reality it has nothing to do with whether the person has taken their medication as prescribed.

There Are State and Federal Lists of Illegal Drugs That Are Considered to Not Affect Driving Ability

Interviewer: Is there a list of common medications that are considered to have no affect on driving or to have an effect on driving?

Brian: There are several lists, one at the state level and one at the federal level, of chemical substances that are considered illegal to use.

Interviewer: They designate between legal and illegal but they don’t designate between having an effect on driving or not having an effect, right?

Brian: Yes, that is correct.

Interviewer: Impair ability, or an impair ability factor, do they assign that to these chemicals?

Brian: They don’t. It’s not like DUI alcohol where they can say if you are above a 0.08 then it is against the law. There is nothing that says that if you are outside a therapeutic level it is against the law. It is simply did it cause impairment or was it present and you were not taking it as prescribed.

The problem with this whole idea is were you taking the medication as prescribed and was it prescribed to you? The problem is the only person who can really testify to that is the person taking the medications.

Can Your Testimony About Your prescription Medication History Help You at Trial?

Unless, for some reason, there is some sort of assistant that is helping the person in taking their prescribed medications. If the only person that can testify to that is the person who is taking the prescribed medications and that person is also the defendant.

Now all of the sudden you get into constitutional issue because the person has a right to remain silent but they are allowed to testify. Do they want to testify? Do they want to evoke their right to remain silent? Should they be punished simply because they evoke their right to remain silent?

There is no one else to testify to whether they are taking the prescription medications as prescribed. Doctors can’t really explain that. You can put on scientists who can say the person was or was not within therapeutic levels.

Again, that doesn’t speak to whether or not the person was taking prescription medications as prescribed. They are the only ones who can testify to that. So in a way it becomes a Catch 22.

By Brian Douglas Sloan

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Brian Douglas Sloan


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Why DUI Attorney Brian Douglas Sloan?


19+ Years SOLELY Focused on DUI Defense


4,200+ DUIs Successfully Defended

Top Accolades

  • Only DUI "Power Lawyer" in the Nation Featured in USA Today, 2022

  • Top 10 in Arizona

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brian sloan on the cover of attorney at law magazine

“I am one of only a handful of Phoenix DUI Lawyers that focuses solely on DUI Defense representation.”

I have spent my entire career SOLELY focused on Arizona DUI Defense Representation, having personally defended more than 4,400 Driving Under the Influence (DUI) clients in the past 19+ years.

If you’re looking for a Divorce Attorney, Tax Attorney, Civil Attorney, etc., I can comfortably say, "I’m not the one for you." I ONLY defend DUI cases in most of Maricopa County, Arizona.

Coming up with traditional, as well as outside-the-box motions and defenses for my clients, often with good results, is the hallmark of my practice.

Lawyers that say they are "aggressive" or "will fight for you" are a dime a dozen. They use these phrases because it is a proven advertising phrase. Being "aggressive" isn’t the same as being good, and is often used to put on a show to hide the fact that they aren’t doing anything meaningful for the client.

The same is true for the Lawyers claiming to do DUI Defense, and Criminal Cases, and Accident Cases, and Divorces, etc. A Jack-of-all-Trades is a master of none! By handling all sorts of cases, they take away from their ability to truly focus on DUIs, and keep up-to-date on the latest changes in DUI Defense Representation.

What I offer is intelligent, quality DUI Defense at an exceptional price. Unlike many other law firms, if you hire The Law Offices of Brian D. Sloan, you actually get me representing you, doing all the work, and working the case. You aren’t hiring one guy with all the experience, but getting the underling with very little knowledge or experience.

I work seven days a week on my client’s cases, and spend hours laying all my thoughts out for my clients in writing, so they can understand their options, and my recommendations. No other DUI Lawyer in the state does this. I try to do what I can to go above-and-beyond for my clients. I hate when the businesses I deal with nickel-and-dime me with hidden costs, and I take pride in not doing that to my clients.

I have not only taught other lawyers how to do DUI Defense Representation at statewide seminars, but I have produced DUI Legal Guides used by defense lawyers across Arizona.

I am one of Arizona's most award-winning DUI Defense Lawyers, as well as being recognized nationally. I was the only DUI Defense Lawyer in the United States named a "Power Lawyer" in a 2022 issue of USA Today

There are no other private Lawyers in Arizona that have personally defended more DUI cases than I have. And as a bonus, I offer a very reasonable flat rate for my legal services, with a payment plan, and without any hidden charges. This guarantees that I offer some of the most competitive rates among all Arizona DUI Attorneys, while being a well-documented and preeminent leader in the field of DUI Defense Representation.

Over the years, countless people have come to me after discovering that their first lawyer made a mistake, gave them false hope or false promises, or simply took their money and didn't do much to advance their case. And you would be surprised at how often this happens.

So, instead of wasting time and money on the wrong DUI Defense Attorney, do yourself a favor and get the proven and well-recognized best DUI Lawyer in Phoenix and the surrounding areas of Maricopa County.

You can reach me on my personal cell phone at 480-720-7839 for a Free ‘In Depth’ Consultation.

I personally defend DUI cases in urban Maricopa County City, Town, and Justice Courts, including:

Ahwatukee / Agua Fria / Arcadia Biltmore / Avondale / Buckeye / Chandler / Country Meadows / Desert Ridge / Dreamy Draw / Downtown / East Mesa / El Centro / Encanto / Gilbert / Glendale / Goodyear / Guadalupe / Highland / Kyrene / Litchfield Park / Maryvale / McDowell Mountain / Mesa / Moon Valley / North Mesa / Peoria / Phoenix / Queen Creek / San Marcos / San Tan / South Mountain / Scottsdale / Tempe / University Lakes / West McDowell / West Mesa / White Tank

For any other Courts in the State of Arizona, including Felony cases, I would recommend my associates on The Arizona DUI Team, whom I work closely with, but I am not the one personally representing the client.

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Brian Douglas Sloan

DUI Attorney

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