drugs and alcohol Taking drugs If you are taking medicines or drugs you should ask your doctor if they will effect your driving. Even some simple cough remedies can cause drowsiness. Read the directions carefully. If in doubt ask at your local pharmacy. Alcohol is a drug that can make you feel over confident and at times less aware of danger. It makes people think that they can achieve the impossible and it can blur judgement of speed and distance. Even small amounts of alcohol will slow down your reactions. it is a major cause of accidents. If you decide to drink the night before your lesson, the amount of alcohol in your body may still exceed the legal limit in the morning