Even Legal Medication Can Lead to a DUI Charge in Florida — What You Don't Know Could Get You Arrested

A lot of people assume that if they're taking their medication exactly as prescribed, there's no way they can be arrested for DUI. I wish that were true. Unfortunately, I've represented many clients who ended up in handcuffs after doing exactly what their doctor told them to do.

Florida's DUI laws don't focus on whether the substance in your system is legal. The law focuses on whether it affects your ability to drive safely. If a police officer believes your "normal faculties" are impaired—regardless of the substance involved—you can be arrested. That includes prescription drugs. And it happens more often than you might think.

Let me explain what the law says, what the police look for, and why having a private lawyer on your side can make a huge difference in the outcome of your case.

Florida Statute § 316.193 – The Law Doesn't Care If the Drug Is Legal

Under Florida Statutes § 316.193, a person is guilty of DUI if they are:

"Driving or in actual physical control of a vehicle within this state, and... under the influence of alcoholic beverages, any chemical substance set forth in s. 877.111, or any substance controlled under chapter 893, when affected to the extent that the person's normal faculties are impaired."

This is the part most people miss: "any substance controlled under chapter 893."

That includes many common prescription medications, like:

  • Xanax (alprazolam)
  • Valium (diazepam)
  • Oxycodone
  • Hydrocodone
  • Ambien
  • Adderall
  • Medical marijuana

Even if the medication was lawfully prescribed to you, if law enforcement believes it impaired your ability to drive, they can arrest you for DUI.

The law doesn't say you have to be taking illegal drugs. It says your faculties must not be impaired by any controlled substance. And Florida law is clear on this point—intent doesn't matter, legality doesn't matter, and your prescription won't shield you from charges.

What Police Look For During a Prescription Drug DUI Stop

If you're pulled over and the officer suspects impairment, here's what typically happens:

  • They'll ask if you've been drinking or taking any medication.
  • They'll observe your speech, eye movement, physical responses, and coordination.
  • They may ask you to step out of the car and perform roadside field sobriety tests.
  • If you don't show signs of alcohol intoxication, they may call in a Drug Recognition Expert (DRE).
  • If they still believe you're impaired, they may arrest you and request a urine or blood test.

You might not even feel impaired. But if the officer thinks your reaction time, judgment, or coordination are affected in any way, you can still be charged.

I've had clients arrested just for admitting they were on prescribed anxiety medication, even with no visible signs of impairment. That's how broad—and how subjective—this area of DUI law can be.

You Can Still Be Sober and Get Arrested

One of the hardest things about these cases is explaining to people that feeling "fine" isn't enough. You might be perfectly coherent. You might have taken your medication hours ago. But if your eyes are red, your balance is slightly off, or you respond slowly to questions, that might be all the officer needs to justify a DUI arrest.

The law is written so that the mere presence of a substance in your system, combined with any perceived impairment, is enough to move forward with charges.

As a private defense attorney, I don't rely on assumptions or appearances. I dig into the details—how long ago you took the medication, what the dosage was, what the officer claimed to observe, and whether any medical explanation accounts for your behavior. If the arrest was based on vague signs, we attack it. If the officer ignored obvious medical factors, we bring that forward.

What About Medical Marijuana?

Medical marijuana patients often think they're protected because they have a card. But that's not how Florida treats marijuana-related DUI arrests.

Florida Statutes § 381.986 allows qualified individuals to use medical cannabis. But § 316.193 still applies. You cannot legally drive while impaired by marijuana—regardless of whether it was prescribed or not.

Marijuana DUIs are especially complex because THC can stay in your system long after the effects have worn off. That means your urine or blood could test positive days after use, even if you weren't impaired at the time of driving. But police and prosecutors often use those results to support charges.

When I defend someone with a medical marijuana DUI, I focus on separating the presence of THC from actual impairment. That distinction is key.

Defenses I Use in Prescription Drug DUI Cases

Every case is different, but there are several strong defense strategies I explore:

  • No actual impairment – If the officer's observations are weak or contradicted by video footage or medical documentation, I push back.
  • Improper DRE evaluation – Drug Recognition Experts often make mistakes, especially if they don't account for medical conditions that mimic impairment.
  • Timing of medication – I investigate when the drug was last taken and how long it typically remains active in your body.
  • No field sobriety test validation for drugs – The standard tests (walk-and-turn, one-leg stand) were designed to detect alcohol impairment, not drugs.
  • Lab results don't support the charge – If the toxicology shows low levels of the medication or therapeutic use, that's a strong argument against impairment.
  • Constitutional issues – If your rights were violated during the stop, search, or arrest, I move to suppress the evidence.

When you're represented by a public defender, they may not have the time to challenge every aspect of the arrest. But when you hire a private lawyer, I focus completely on your case. I look at everything—from the way the officer described your speech to whether the lab handled your sample properly. Those details matter.

Why Private Legal Representation Matters in Prescription DUI Cases

Prescription drug DUI charges are often based on interpretation. There's usually no breath test result. The evidence may be nothing more than an officer's opinion and a toxicology report that confirms the presence of a prescribed substance. That's not the same thing as proof of impairment.

When you have a private lawyer, I can get ahead of the prosecution. I don't just wait for court. I file pretrial motions, gather medical records, consult experts, and challenge the arrest from every angle. In many cases, we can get the charges reduced—or dropped entirely—before trial even becomes an issue.

A DUI conviction in Florida stays with you forever. It can never be sealed. It can never be expunged. That's why these cases need to be taken seriously, even if you were just following your doctor's instructions.

FAQs – DUI Charges Involving Prescription Medication in Florida

Can I still be charged with DUI if I have a valid prescription for the drug in my system?

Yes. Florida law doesn't make an exception for prescribed substances. If the police believe your ability to drive was impaired by the medication, they can charge you with DUI—even if you're taking the drug exactly as prescribed.

What if I wasn't feeling impaired at all?

You might have felt fine, but the officer may have seen something they considered a sign of impairment. That could be slower speech, poor coordination, or confusion. Even fatigue or anxiety can be mistaken for drug effects. These observations are highly subjective, which is why your defense lawyer needs to review the video footage, police report, and any medical records that explain your condition.

Will the fact that the drug was prescribed help my case?

It can help if your attorney frames the issue correctly. While the prescription doesn't automatically excuse the impairment, it shows the drug was legally taken. That gives us room to argue that you were not impaired, especially if the dosage was low or taken long before the stop. But without a strong legal argument, the prescription alone won't prevent conviction.

How do the police determine if I'm impaired by medication?

If you blow 0.000 on the breathalyzer but still show signs of impairment, officers often bring in a Drug Recognition Expert (DRE) to conduct a multi-step evaluation. This includes eye tests, divided attention tasks, checking pulse and blood pressure, and interviewing you. Their final opinion, paired with a urine or blood test, can be used to support a DUI charge.

What happens if the lab test shows my medication in low amounts?

If the concentration is low and consistent with therapeutic use, your lawyer can argue that there was no actual impairment. Just having a substance in your system doesn't prove you were unsafe to drive. That's an important distinction in DUI drug cases, and it's a defense that can result in reduced charges—or dismissal altogether.

Can I lose my license for a DUI based on prescription drugs?

Yes. A DUI conviction for drug impairment carries the same penalties as an alcohol-based DUI. That includes mandatory driver's license suspension, even for a first offense. You may also be required to complete DUI school, community service, and substance abuse evaluation—even if the drug was legal.

Should I hire a private attorney for this type of DUI?

Absolutely. Prescription drug DUI cases often depend on challenging the officer's assumptions and the interpretation of toxicology results. A private defense attorney can investigate the case in ways that public defenders may not have time to do. That includes questioning the DRE's qualifications, obtaining your medical records, and exposing weaknesses in the state's evidence.

How long do prescription drug DUI cases take to resolve?

It depends on the complexity of the case and the county you're in. Most take several months, but the earlier you hire a lawyer, the sooner we can start pushing for a favorable outcome. Some cases can be resolved quickly through pretrial motions or negotiations. Others may go to trial, especially when the evidence is weak but the prosecution won't back down. Either way, early action gives you more control.

Contact Musca Law 24/7/365 at 1-888-484-5057 For Your FREE Consultation

If you've been arrested for DUI and you were only taking your prescription medication, don't assume the charge will go away. You need a defense strategy that's built on facts—not assumptions.

Musca Law, P.A. has a team of experienced criminal defense attorneys dedicated to defending people charged with a criminal or traffic offense. We are available 24/7/365 at 1-888-484-5057 for your FREE consultation. We have 30 office locations in Florida and serve all counties in Florida.