Share on Facebook

7 Things You Need to Know to Avoid Drugged Driving

It's easier than you think to become a drugged driver. A family doctor offers advice.


Which classes of drugs are most likely to cause car accidents?

Golfer Tiger Woods had five different drugs in his system when he was arrested for DUI earlier in 2017. But he’s not alone. Dependence on prescription drugs and over-the-counter medicines is leading to addiction, lives being ruined, and a huge rise in accidental deaths from overdosing. The involvement of opioid painkillers in fatal car crashes rose seven-fold in the ten years from 2005 to 2015.

In the Roadside Survey of Alcohol and Drug Use by Drivers (2014), 25 percent of drivers tested positive for a drug which could impair their driving. There was a 47 percent rise in drivers testing positive for marijuana (legal in some states), and users were 25 percent more likely to be involved in a crash.

We all know the dangers of drunk driving—one third of all highway deaths are linked to alcohol. The law is clear that driving with a blood alcohol concentration (BAC) over 0.08 is illegal in every state. But the law is much less clear about drugged driving and regulations vary between states.

This is partly because assessing the impact of drugs on the system is much harder to quantify than alcohol—the effect varies greatly between people. Unlike drunk driving, most drugged driving occurs during the day, and many instances occur because the driver is unaware that prescription or OTC medication can impair driving even when you’re within the safe dosage.

Ankrehah Trimble Johnson, MD, a family physician at Brownstone Total Family Care in Alabama, explained how easy it is to end up drugged driving unwittingly. She cites the example of using antihistamines to treat seasonal allergies:

“People take it early in the morning because the sinuses can be worse after you’ve laid back at night in the bed,” she says. “So you take this on the way out the door, and as you’re driving to work, you can experience some sleepiness and lethargy, because those antihistamines can definitely cause you to have a lot of sleepiness. All you’re trying to do is get through your day, but it really can impair your driving and really can affect you.”


Sedatives, painkillers and antidepressants

Obviously, sedatives such as benzodiazepines, barbiturates, and sleep medications can have an impact on your driving. The host of potential side effects includes: dizziness, drowsiness, slurred speech, poor concentration, confusion, movement and memory problems, lowered blood pressure, and slowed breathing.

Many painkillers, especially opioids like codeine, Fentanyl, Vicodin, and Demerol will make you sleepy and lethargic too. Other possible side effects include nausea, euphoria, confusion, and slowed breathing. This is what doctors should tell you about pain meds.

Paracetamol-based medicines like Tylenol have a similar effect, and many people don’t realize that while ibuprofen is safe at the OTC dosage of 200mg, larger doses (such as the prescription strength 800mg), can affect your driving.

Some antidepressants can also cause drowsiness, especially when you begin taking them.


Allergy and cold medication

As Dr. Johnson explains, allergy medication like Benadryl can make you sleepy, especially if you take it first thing in the morning before driving to work. They can also make you unfocused, and slow down your reaction time, making you vulnerable to accidents. Watch out for these other common medication mistakes.

OTC cough and cold medications are usually safe at the recommended dose, but taking too much can cause a psychoactive reaction.


Anti-sickness and antidiarrheals

Tablets to ward off nausea or travel sickness are well-known for causing sleepiness, but many people don’t realize that antidiarrheals like Imodium also contain sedatives which could affect your driving. Maybe try one of these natural remedies for diarrhea instead.



Prescription stimulants such as Ritalin and benzadrine won’t cause sleepiness, but they can have other health risks. At their prescribed dose they make you more alert, but an overdose can cause high body temperature, irregular heartbeat, heart failure, and seizures.

For more details on specific medicines, check out guidance at the National Institute on Drug Abuse.


Who is most at risk of unwitting drugged driving?

Anyone can be at risk of drugged driving if they don’t pay attention to the correct dosage, but some people are more vulnerable to side effects from prescription and OTC medicines. Older people are often affected more strongly, as well as those who have reduced liver or kidney function. They’re also most at risk for the dangers of polypharmacy.

“A lot of medications are cleared through the kidneys,” Dr. Johnson says, adding that it takes longer for medication to clear the body if the kidneys aren’t working efficiently.

“Tylenol is cleared through the liver,” she adds. “So if you’ve got liver issues, that’s going to slow the passage of the Tylenol getting out of your system.”


How to avoid accidental drugged driving

Dr Johnson has two recommendations to help drivers avoid accidental drugged driving. The first is to take medication containing sedatives in the evening rather than first thing in the morning. “Taking the medicine at night can actually help to ease up those symptoms and alleviate that sleepiness,” she said.

Secondly, be sure to discuss the issue with your doctor. If you’re prescribed any kind of new medication, ask about possible side effects and whether a different prescription might be better. Ask if it can be taken at night rather than during the day.

And if you’re considering OTC medication, her advice is also clear: “My recommendation is to call your physician and say ‘If I am going to reach for something over the counter, what is the most that I can take safely?'”

Elizabeth Manneh
Elizabeth Manneh is a freelance writer focusing mainly on healthcare, digital health & technology, and health & wellness. Her work has been featured on Readers Digest, MSN, AOL, The Family Handyman, and Paysa. A retired primary school principal and education consultant, Manneh has a continuing passion for education and learning. Visit her website: Elizabeth Manneh.

Newsletter Unit

CMU Unit