Meningococcal sepsis

A patient is brought to the emergency department:
A man, 19 years old, on his way to A&E, accompanied by a roomate, became very restless even agitated, loosing consciousness. Called EMS. At the arrival of EMS the patient was unconscious (GCS 1-1-4). He was intubated, ventilated and intravenous catether was inserted. The history was taken from the roomate. Two days ago there was a party and all were binge drinking. Next morning, the patient complained about headache, weakness, joint and back pain and fever. His condition got gradualy worse. Four hours later petechial rash appeared on a lower and upper limbs. According to this medical history there is reasonable suspicion of invasive meningoccocal disease. Which antibiotic and in what dose are indicated in a suspition of IMD?
19
years
man
RR
25 /min
HR
125 /min
SpO2
96 %
BP
100/60 (73) mmHg
Examination
Patient unconscious, petechial rush on upper, lower extremities and on the trunk; Lungs: alveolar breathing sounds, Heart: regular heart beat, tachycardia, capillary refill: 2.5 sec, cold peripheries
Glycaemia
Gly
7,0  mmol/L
Glycaemia
Take a sample