A 46-year-old man presented to the casualty with acute onset of seeing lizards all all around him in the room. He has been violent towards members of his brother who tried to bring him to hospital. On history he has a longstanding history of drinking alcohol and using cannabis for 7 years. He had missed his drinks for the last 3 days. On examination his blood pressure is high and he has global confusion. Which of the following can be used in the immediate treatment of the condition?