Final answer:
Drugs that cause drowsiness, such as depressants, opioids, anxiolytics, and certain antidepressants and stimulants, impair driving abilities and shouldn't be taken before driving.
Step-by-step explanation:
Drugs that may cause drowsiness and should not be taken before driving affect basic driving skills because they can depress the central nervous system. These can be prescription or over-the-counter medications, and their consumption can lead to impaired driving abilities. Some known drugs that cause drowsiness include depressants such as ethanol (found in alcoholic beverages), opioids (like codeine and heroin), anxiolytics (such as benzodiazepines), barbiturates, and certain antidepressants. Additionally, it's important to note that even stimulants can have after-effects that can impair driving, such as the crash later following heightened alertness. Therefore, understanding the impact of these substances on driving skills is critical for road safety.