Published on July 23, 2018

Be alert about this driving hazardBe alert about this driving hazard

Drivers, take notice.  Getting behind the wheel after taking some medicines can slow your responses and impair your ability just as if you had been drinking alcohol.

Which ones?

Some medicines commonly used for the following conditions may make you drowsy, dizzy, nauseas or unable to concentrate, according to the U.S. Food and Drug Administration [pdf], such as:

  • Allergies
  • Anxiety
  • Colds
  • Depression
  • Muscle spasms
  • Pain
  • And others

“One example is Benadryl, which is great as an antihistamine if you have allergies, but Benadryl is also a common ingredient in sleep aids. It can make people drowsy, sedated, and can affect the ability to operate a vehicle,” said James Mangan RPh., MBA, director of Hospital and Ambulatory Pharmacy at Cape Cod Healthcare.

Read Labels

Prescription and non-prescription medicines (those you can buy “over-the-counter” at any store, pharmacy, or online) can have side effects that might surprise you.  To learn about these drugs and their side effects, Mangan recommends that you:

  • Read medicine labels and instructions carefully.
  • Discuss all the medications, vitamins, supplements and herbal remedies with your prescribing doctor, and follow doctors’ orders.
  • Talk with a pharmacist.

Research published in the Journal of Studies on Alcohol and Drugs warned that many people taking prescription drugs are not aware their meds could impair their ability to drive.

Close to 20 percent of U.S. drivers are taking prescription drugs, the study showed. Of those who took prescription sedatives and narcotics, slightly more than 85 percent said they had received information about potential impairment.

However, just 57.7 percent of people who had been prescribed stimulants had been told about possible impairment.

The study concluded that there are missed opportunities for informing people about driving-related risk associated with their medications.

Mangan offered the following advice when it comes to taking medications and driving:

Everyone reacts differently

“Just because your friend takes an allergy pill and has no side effects doesn’t guarantee you can take the same pill and feel the same. Side effects vary from person to person because everyone metabolizes medicine differently,” he said. This applies to all medication, not just allergy pills.

Read and heed the warnings

Pharmacists often put stickers on bottles alerting that the ingredients in the medicine “may cause dizziness,” “may cause drowsiness,” and other cautions. Don’t ignore those warmings and always read instructions, Mangan said.

Understand additive effects

Be aware: One common medication can contain more than one ingredient. For example, cough syrups that contain pain relievers and Benadryl are examples of combination drugs.

Be doubly aware: Medicines can have additive effects; that is, taking two different medicines can magnify the effects. For example, someone who takes pills for anxiety (Xanax or Prozac, for example) can become extremely tired if they also take an over-the-counter cold remedy that contains Benadryl, Mangan said.

Start off slowly

Never drive after trying a new medicine; wait and see how it affects you, Mangan warned.

“When I worked as a retail pharmacist, I constantly had to caution people not to get behind the wheel of any vehicle until they knew how a new medication made them feel.  Some medicine should never be taken if you are driving, and you need to work with your doctor or healthcare provider to deal with this or find alternatives,” he said.

Ask a pharmacist

“Be cautious and aware,” Mangan said. “Medicine can help immensely, when used correctly. Because everyone is different, I can’t encourage enough the importance of talking with a pharmacist.”