Drug
drugs
A toxin.
"a (harmful) substance with an inherent property that tends to destroy life or impair health"Information taken from: www.dictionary.com
Only conditions that would impair your driving, like epilepsy, would be a problem. Otherwise, they will not be picky over your health.
It depends. Any substance, such as alcohol or drugs, prescription or otherwise, that influence/impair your driving can violate state laws. The idea is that if you are not safe to drive you should not be driving. It's an issue of public safety. If you have something in your system that COULD impair your driving, then the next step is to determine if it DID impair your driving. A few ounces of beer with a meal would probably not influence/impair your driving. As you increase the concentration you make the influence/impairment more likely. Same with drugs. The short answer, low dose, less likely to impair, high dose, more likely to impair.
YES! It is very bad for you and can do a lot more damage than that. I would not suggest it! If you are referring to 'spice' as simply a substance, like rosemary or thyme or cayenne, actually, spices are very beneficial to the health, specifically for circulatory system and neurological health. If you are referring to an illegal drug, such drugs are illegal because they have dangerous health effects. Any drug can permanently impair brain function.
impair=hinder, impede
Alcohol over indulgence can impair liver function, and sap potassium levels.
Too much marijuana will impair your vision. Only a little bit will impair your judgement.
The unbearable stench in the air seemed to impair her senses.
Kill and injure have several synonyms. Kill has murder, terminate, and defeat. Injure has maim, deface, harm, impair, and wrong.
Driving fitness can be impaired by the following: fatigue, ill health, distractions in the vehicle, drugs/alcohol, emotions (anger, sadness, fear).