Cocaine and Coffee are two drugs, one being illicit and one being legal which have several benefits for boxers. Both cocaine and coffee would help you in a fight for several reasons. However both also have potential negative effects which kick in around one hour after these are consumed. I will go over what happens to fighters who take these and why boxers have taken these substances in the past.
Coffee: Coffee provides a natural high. Similar to cocaine it elevates the heart rate, to a lesser degree. Coffee has some negative effects. Despite initially providing more energy, coffee causes dehydration. So if boxers drink coffee before a bout they may have excess energy for the first couple of rounds but they will dehydrate and cramp up quicker. Drinking coffee for a fighter is totally counter productive in terms of what they are trying to achieve.
Cocaine: Cocaine has less dehydrating qualities. This substance is illicit, highly addictive and a massive problem for societies across the world. Cocaine gets the heart rate up very high and provides adrenaline throughout the body. Adrenaline provides a huge boost in taking punishment such as punches. When a boxer who is high on cocaine takes a punch, the effect of this punch would be less than normal. A feeling of invincibility accompanies adrenaline throughout the body. Taking cocaine before a bout would have some very negative impacts. Despite facing a huge ban as the substance is illicit in boxing just as it is throughout society. It’s likely to make a fighter angry which leads to losses of concentration. In boxing concentration is everything especially for counter punches in high quality bouts.
So the short answer is. Both Cocaine and coffee would help a boxer or normal person in a fight. Both get your heart rates up, however drinking Coffee dehydrates people quickly and if a boxer did this before a bout they would feel lethargic and cramp up a lot earlier than normal. As for a boxer taking cocaine before a bout and if that would help in a fight. Well it would help in a big way. The increased adrenaline could make a domestic level fighter perform like superman on the international arena. It would be rather obvious if a fighter was under the influence of drugs at a post fight interview or press conference, by the incoherent ramblings which accompany cocaine users.