what’s the most dangerous drug in the world and has the most significant side effects to the human body psychically and

Question: what's the most dangerous drug in the world and has the most significant side effects to the human body psychically and mentally ?
- Keywords:
  danger,
  drug,
  mentally,
  psychically
Asked by jackson123308 to Ross on 16 Nov 2015.
- Ross King answered on 16 Nov 2015:
  
  Hey Jackon,
  
  Tough question! You might be surprised by me saying this but I (and others) believe that alcohol is one of the most damaging drugs, both to the body, the brain and to others. Alcohol is safe if you take care when you drink it (and if you’re over 18!) but alcoholics are in danger of having many different problems. It is such a dangerous drug because it is so easy to take and, of course, it is totally legal.
  
  As for other chemicals that are very dangerous, there is a toxin that comes from some kinds of pufferfish that I have worked with in the past. It is called tetrodoxotin (TTX) and it stops your nerves from working properly, which will kill you very quickly. So be careful if you order any sushi in the future that it is prepared and cooked properly 😛

Question: what's the most dangerous drug in the world and has the most significant side effects to the human body psychically and mentally ?