Is It Possible to Get a DUI in Illinois on Prescription Medication?

Legal Use Doesn’t Mean Legal Driving—Here’s What You Need to Know

Driving in Illinois after taking your prescribed medication may seem completely legal—and often, it is. But what many people in Chicago don’t realize is that the same medication their doctor told them to take can still lead to a DUI arrest. Illinois law doesn’t care whether your prescription is valid. It only matters whether law enforcement believes that the medication impaired your ability to drive.

Every year, drivers across Cook County are pulled over and charged with DUI—not because they were drinking, and not because they were using illegal drugs, but because they took medication as directed. Whether you’re prescribed Xanax, Vicodin, Ambien, Adderall, or any number of other medications, you can be charged with driving under the influence if an officer believes it affected your ability to operate a vehicle safely.

If this has happened to you, or if you’re wondering whether it can happen, the answer is yes. But there’s also good news: these cases are defendable, and a skilled DUI defense attorney in Illinois can often build a strong case to avoid a conviction or even get charges dismissed.

Illinois DUI Law Covers More Than Just Alcohol

Under 625 ILCS 5/11-501, it is illegal to operate a motor vehicle while:

• Under the influence of alcohol,
• Under the influence of any intoxicating compound,
• Under the influence of any drug or combination of drugs,
• Or under the combined influence of alcohol and any other drug(s) to a degree that renders the person incapable of driving safely.

This statute clearly doesn’t distinguish between illegal drugs and prescription drugs. If the drug impairs you, you can be charged. That means you can be arrested and prosecuted even if you have a doctor’s note, a filled prescription bottle, and no intention of doing anything wrong.

In fact, Illinois law is more concerned with the effect the substance has on your driving than the source of it. From the police officer’s perspective, it doesn’t matter if you were prescribed the medication. If you were unable to drive safely, and they can support that with evidence or observation, they may issue a DUI.

How a DUI on Prescription Medication Begins

Most prescription-based DUIs start like any other traffic stop. You might be pulled over for speeding, lane drifting, running a stop sign, or getting into a minor accident. During the stop, the officer will observe your behavior. If you appear drowsy, confused, slow to respond, or uncoordinated, they may begin a DUI investigation.

You might be asked whether you’ve taken anything. Many people think it’s safe to say, “Yes, my pain medication,” or “I took a sleeping pill last night.” Unfortunately, those statements often give the officer all they need to continue with a DUI arrest—even if you didn’t violate the prescription.

If a Drug Recognition Expert (DRE) is called to the scene or evaluates you at the station, their report will heavily influence whether the state files charges. You may also be asked to provide a blood or urine sample. Even without a positive test result, a combination of your statements, officer observations, and field sobriety test results can lead to criminal charges.

The Penalties Are the Same as Alcohol-Related DUI

A prescription DUI carries the same penalties as an alcohol-related offense. For a first offense, it’s a Class A misdemeanor, which may include:

• Up to 364 days in jail
• A maximum $2,500 fine
• Court supervision, probation, or conditional discharge
• Mandatory drug or alcohol education
• Suspension of your Illinois driver’s license
• Community service or victim impact panels

If you have a prior DUI conviction, were driving with a child in the car, caused an accident with injuries, or have other aggravating factors, the charge can become a felony—also known as Aggravated DUI.

Even if you avoid jail, a conviction for DUI will stay on your criminal and driving record permanently. Illinois does not allow DUI convictions to be expunged or sealed. That’s why a strong legal defense is critical.

What Prosecutors Need to Prove

In order to convict you of DUI for prescription medication, prosecutors need to show that:

• You were in actual physical control of a vehicle
• You were impaired due to a drug or combination of drugs
• That impairment rendered you incapable of driving safely

They do not need to prove that your medication was illegal. Nor do they need to prove that you exceeded the prescribed dosage—though that may be used as evidence. The standard is impairment, and that makes these cases very subjective.

There’s no breathalyzer for most prescription drugs. Lab tests may detect the presence of the drug in your system, but not how impaired you were. That means a good defense attorney has multiple ways to attack the evidence and prevent the state from meeting its burden of proof.

Common Defenses in Prescription DUI Cases

Defending against a prescription-based DUI in Illinois requires a fact-intensive, strategic approach. Some of the most effective defenses include:

Lack of Probable Cause – If the officer had no legal justification for pulling you over in the first place, any evidence obtained after the stop may be suppressed.

No Clear Signs of Impairment – Just because a person is tired or distracted doesn’t mean they were impaired. A lawyer can challenge the officer’s observations and bodycam footage.

Lawful Prescription, No Warning Labels – If the medication did not warn against driving or was taken properly, that can help negate the prosecution’s theory.

Alternative Explanations – Fatigue, anxiety, stress, illness, or other conditions may explain behavior mistaken for drug impairment.

Unreliable DRE Testimony – DREs are not doctors. Their evaluations are based on subjective criteria and can be challenged with cross-examination or expert testimony.

Flawed Blood or Urine Testing – Testing procedures may be outdated, contaminated, or misinterpreted. Toxicology experts can point out weaknesses in the lab results.

Why You Shouldn’t Handle a Prescription DUI Alone

It’s tempting to think that you can explain your way out of a charge like this. “It was my medication,” or “I didn’t feel impaired” seem like reasonable defenses. But once the state has charged you, they’re not interested in explanations—they want a conviction.

You need a lawyer who understands how DUI law works when it comes to prescription drugs. That means knowing how to interpret medical records, challenge lab reports, and discredit officer testimony. It means someone who can present your use of medication in the right legal context—not just as an excuse, but as a non-impaired, lawful activity.

Without an attorney, you may find yourself accepting a plea deal that turns a legally valid medication into a permanent criminal record.

The Importance of Hiring a Chicago-Based DUI Attorney

Laws don’t change from city to city, but judges, prosecutors, and police procedures do. In Chicago, your defense is strengthened when your attorney knows the Cook County courts. An attorney who practices regularly at the Daley Center or 26th and California understands how to file motions, when to push for hearings, and what types of arguments resonate with local judges.

At The Law Offices of David L. Freidberg, we’ve represented hundreds of clients in DUI cases involving prescription drugs. We know the tactics the prosecution uses, and we know how to fight back.

Call Now – The Law Offices of David L. Freidberg Is Ready to Help

If you were arrested in Chicago for DUI, protect your future by contacting The Law Offices of David L. Freidberg. We have decades of experience handling DUI cases in Illinois. Our firm is available 24/7 to provide the legal defense you deserve.

Contact us today at (312) 560-7100 or toll-free at (800) 803-1442 for a free consultation. We’re available 24/7 to serve clients throughout Illinois, Cook County, DuPage County, Will County, and Lake County.