Impaired driving
Most people know that driving while impaired by alcohol is against the law in Canada. Not so many realize that driving while impaired by any drug is a crime.
Alcohol is the most widely used drug and the one most often linked to motor vehicle accidents. But other drugs too - and especially when they are combined with alcohol - can affect the way you drive.
It makes sense. Driving requires attention, judgment, perception, decision-making, physical reaction - and the ability to coordinate these skills, drivers under the influence of any drug that alters behavior, or mood, may be dangerous behind the wheel or operating any other complex machinery.
A 1992 study by the Addiction Research Foundation discovered that, after alcohol, the drugs most commonly found in accident victims were: cannabis (e.g., marijuana and hashish), benzodiazepines (e.g., tranquillizers), and cocaine. Other drugs found were: morphine, barbiturates, codeine, meperidine (e.g. Demerol), diphenhydramine (e.g. Benadryl), and pheniramine, an ingredient in many cold preparations.
Some drugs prescribed for medical reasons have little or no effect on driving if they are taken by themselves and in the recommended doses. Many others, however, can affect how you drive, even when they are taken in recommended doses. Some carry a warning to be careful if you are going to be operating complex machinery.
Depressant drugs, such as tranquillizers, sedatives, or sleeping pills, slow down your central nervous system. They can therefore make you drowsy, slow your reaction time, and hinder your ability to pay attention or concentrate.
The same is true for drugs with depressant side effects, drugs such as cold remedies, cough medicines, antihistamines to control allergy symptoms, and drugs to prevent nausea or motion sickness.
The sedative effect of some antidepressant drugs can also affect your driving ability.
Mixing any depressant drug with alcohol, which is also a depressant, can be extremely dangerous. The combined effects of the two drugs are sometimes much greater than the effect of either one alone.
You might think that because depressant drugs add to the depressant effect of alcohol, stimulants would counteract this effect. This is not the case. Only time can lessen impairment - by lowering the alcohol concentration in your blood or the level of any other drug in your system.
Stimulants such as the caffeine in coffee, tea, cola drinks, or "stay awake pills" may make you more alert, but they leave you still impaired. Also, their effects may wear off quickly, leaving someone who is very tired asleep at the wheel.
Although basic driving skills do not seem to be affected by medical doses of amphetamines, these stimulant drugs make some people over-confident, which may lead to risk-taking driving. High doses of amphetamines make some people hostile and aggressive, which may also result in risky driving behavior.
Some believe it is safer to drive under the influence of cannabis than of alcohol. However, like alcohol, marijuana and hashish impair the skills important for driving, mostly those necessary for perceiving and responding to potentially hazardous situations. And their effects can last for hours, long after the "high" is gone.
Many cocaine users say the drug actually improves their driving ability. This is not surprising. Cocaine is a drug that makes many people feel they have greater mental and physical abilities than they actually do. Cocaine also dramatically affects vision, and some users have complained of sound or smell hallucinations - they hear bells ringing or smell smoke or gasoline, for example. These hallucinations have caused them to drive dangerously.
The best advice for anyone using illicit drugs or legal drugs in a non-medical way is...don't, and certainly not if you intend to drive. Illicit drug users usually can't be sure what drug or drugs they are taking or of the dose they are getting.
Best advice for anyone taking any medication, prescribed or over-the-counter, is...ask a pharmacist or doctor about how the drug might affect you and your driving and whether even a small amount of alcohol will increase the drug's effects on your driving ability. Be aware, too, that the same drug can affect you differently at different times.
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