Does BAC Measure Prescription Medications?

California's DUI law prohibits driving while under the influence of not only alcohol but also drugs. It does not distinguish between illegal controlled substances and prescription medications. If you take something your doctor prescribed and it affects your driving ability, you could be charged with DUI. With alcohol DUIs, authorities will often rely on the results of breath or blood tests to determine a person's blood alcohol concentration (BAC) and support claims of drunk driving. However, a prescription medication is unlikely to affect BAC. So how do prosecutors attempt to prove DUI of drugs? They may rely on other evidence, such as the arresting officer's observations.

If you have been accused of driving under the influence, contact our Los Angeles attorneys at Lessem, Newstat & Tooson, LLP by calling (800) 462-7160.

You Can Get a DUI on Prescription Drugs

Driving under the influence means not only drunk but also drugged driving. Drugs, including prescription medications, can affect your ability to operate your vehicle safely.

Some medicines cause a range of side effects, including:

  • Drowsiness,
  • Dizziness,
  • Nausea, and
  • Blurred vision.

Poor vision and coordination, reduced reaction time, and lack of concentration can make driving tasks such as staying in one lane, obeying traffic signs and signals, and maintaining proper speed and distance difficult, if not impossible. Because of this, some prescriptions have warnings against getting behind the wheel after taking them.

If you get behind the wheel after taking a prescription that makes you unable to control your vehicle, you can get a DUI.

How Alcohol Is Measured in a DUI

If an officer legally arrests you on suspicion of driving under the influence of alcohol, they will direct you to submit to a breath or blood test. These analyses are used to determine your BAC. A breath test is an indirect measure of BAC, as it analyzes the air deep within your lungs and generates an estimate of alcohol levels in your system. A blood test is more accurate because it directly assesses the amount of alcohol in your blood. However, it's also a more invasive test.

Regardless of the chemical test you're subjected to, a BAC of 0.08 or more violates the DUI per se laws, as you are legally considered to have driven while intoxicated. The prosecutor will present this number in court to prove you are guilty of DUI.

A Prescription Medication May Not Affect BAC

Breath and blood tests measure alcohol concentration. Although some prescription medications contain alcohol, it's likely not enough to get your BAC to 0.08 or higher.

Still, a lack of BAC at or above the legal limit may not allow you to avoid a DUI charge. Remember that a DUI isn't only triggered when someone's BAC is 0.08 or more. It can also occur when a driver was so affected by a substance, they were unable to control their vehicle safely.

Suppose you took a breath test, but your BAC was below 0.08. The officer might still suspect that you were impaired, not by alcohol but by some other substance, because of your driving behavior and physical attributes. In that case, they may order you to submit to a blood or urine test. The purpose of these tests is to detect the presence of a drugs.

Although the prosecutor might not have an elevated BAC to present in court, they can introduce other evidence to attempt to prove a DUI of drugs.

Some of the materials they might present include:

  • Chemical test analysis showing the presence of a drug in your system,
  • Testimony from the officer concerning your driving behavior and conduct during the initial stop,
  • Testimony from witnesses, and/or
  • Reports from a drug recognition expert (DRE).

Retain Legal Representation

DUI matters can get tricky if you have been accused of driving under the influence of a prescription medication. Defending these cases requires a thorough look at the facts, including a close review of the chemical test results and the machines used for the analysis. A criminal defense attorney can help with the details of your case, gathering and preserving evidence to build a legal strategy for you.

To speak with one of our Los Angeles lawyers about your situation, please call Lessem, Newstat & Tooson, LLP at (800) 462-7160 or submit an online contact form today.