The Effects of Drug Use on Driving Performance

Driving and drug use

‘I drive better when high.’

How many times have you heard a variation of the above claim? People who use substances as diverse as weed, cocaine, and opiates often say this and believe it. At the very least, they consider the effects of drug use on their driving performance to be minimal. This is often in contrast to drunk driving, which people tend to take more seriously.

Is there any merit to this claim? Or do drugs actually worsen driving performance?

Unfortunately, as too many people have found out the hard way, almost all drugs have a negative impact on driving performance. They can lead to slow reaction times, recklessness, and bad decision-making.

To underscore how important it is not to drive under the influence of substances, here is how they affect your driving performance.

How Drugs Affect Cognitive and Motor Skills

Safe driving requires peak cognitive and motor skills which are impacted by drug use. Reaction time, decision-making, and coordination are all essential when responding to road conditions, traffic signals, and other drivers. Depending on the drug, the effects can range from mild to severe, but all drug use behind the wheel compromises safety.

They do so in the following ways:

Cognitive Impairment

Drugs, especially depressants, can slow mental processing. A driver may take longer to make the decision to brake or swerve. Their ability to gauge distances or anticipate road hazards is also diminished. Stimulants, conversely, may induce overconfidence or aggressive driving behaviors, creating a false sense of control.

Motor Skill Impairment

Both legal and illegal substances can affect coordination and physical control. These motor skills need to be at a high level of functioning in order to maintain lane position, make controlled turns, and adjust speed. Drugs that impair muscle control, such as opioids or muscle relaxants, make tasks like steering or applying the brakes more difficult.

Plus, reaction time is slowed by many substances and even a slight delay can be catastrophic in situations where immediate action is needed.

Common Drugs and Their Impact on Driving

Different types of drugs have different effects on the body and mind, which translate to specific driving impairments. Below are some of the most common substances that impair driving performance:

  • Marijuana:

    The increasing legalization of marijuana has positive benefits. Marijuana can be used for medical purposes. Also, many marginalized people have ended up serving jail time in the past for possession of marijuana, which should not be seen as a major offense. However, it is prudent to be concerned about its impact on driving. Marijuana affects motor coordination, tracking ability, and attention span. Studies show that marijuana also alters perception, making drivers misjudge time and distance.

  • Prescription Drugs:

    Medications prescribed for legitimate medical purposes can still impair driving. Opioids, benzodiazepines, and certain sleep aids (like Ambien) are particularly dangerous. These drugs cause drowsiness, dizziness, and impaired motor function. In some cases, individuals may not be aware of how significantly their driving skills are impaired while on these medications, posing a hidden threat on the road. For many users, especially those who are new to the medication, driving might even be impaired the following day.

  • Cocaine and Other Stimulants:

    Stimulants like cocaine, amphetamines, and methamphetamines increase alertness and confidence, which can lead to reckless driving and risk-taking behaviors. These substances often cause drivers to overestimate their abilities, making them more prone to speeding, aggressive maneuvers, or tailgating. Additionally, the ‘crash’ phase after stimulant use leads to extreme fatigue and impaired concentration, creating dangerous conditions on the road.

  • Hallucinogens:

    Drugs like LSD, magic mushrooms, or PCP cause distortions in perception, hallucinations, and delusions, making it impossible to safely drive a vehicle. Driving while under the influence of these substances can cause the person not to perceive reality correctly, misjudge speed and distance, and respond to imaginary stimuli. Hallucinogens are some of the most dangerous drugs in the context of driving.

Drugged Driving vs. Drunk Driving

Drunk driving is, rightly, considered extremely dangerous. But does that mean driving while under the influence of drugs is less dangerous?

There are differences, but driving remains dangerous in both situations.

  • Differences in Effects:

    Most people know how alcohol impairs motor coordination, decision-making, and reaction times. In contrast, many people don’t know that much about drug impairment. They also may not appreciate the difference in how differing substances affect the brain.

  • Detection and Enforcement:

    It is relatively straightforward to measure drunk driving through breathalyzers and BAC levels. Drugged driving is more difficult to detect because impairment levels vary depending on the substance, and there’s no simple test that can be applied roadside for all drugs. Law enforcement may need to conduct blood tests, urine tests, or call in drug recognition experts to assess impairment. Since many substances remain in the person’s system for days or weeks after usage, it is often impossible to determine whether they were under the influence when they were driving.

  • Legal Consequences:

    Laws around drunk driving are well-established but legislation for drugged driving is still playing catch up, especially with the legalization of substances like marijuana in some regions. Nonetheless, the penalties for drugged driving are similar to those for drunk driving in many areas, including heavy fines, imprisonment, and suspension of the driver’s license.

Conclusion

Next time you hear someone say that they drive better when on drugs – or even when you have the thought yourself – remind them that this is unlikely. Drugs impair driving performance in a number of ways, including making it difficult to physically function at peak levels and distorting decision-making.

Never drive under the influence of substances, even those that are legal. If you are unsure whether you are in a good position to drive, always err on the side of caution.