0.01 mg/kg. It has quick onset of action, and common side effects are: increased heart rate, dry mouth, flushing, and urinary retention. Lidocaine – It is used to reduce the sympathetic response in those who have suspected raised intracranial pressure (ICP) or those who received succinylcholine which also causes increase ICP or those with underlying asthma that have bronchospasm. Administration of lidocaine can causes reduction in mean arterial pressure (MAP). The dosage is 1.5 mg/kg. This drug is metabolized by liver. The side effects are: hypotension, arrythmia (irregular heart beat). Lidocaine can further interact with other drugs such as amiodarone and monoamine oxidase inhibitor to cause hypotension, and dronedarone to cause arrhythmia. Induction agents Administration of induction agents followed by neuromuscular blockade agents helps to achieve optimal conditions for intubation. Etomidate – It is an imidazole-derivative that stimulates GABA receptors. The dosage is between 0.2 and 0.6 mg/kg (commonly 20 to 50 mg doses). Dose reduction may be required in those with hypotension. Etomidate has minimal cardiovascular side effects, reduces intracerebral pressure (by reducing cerebral blood flow), and does not cause histamine release. It has quick onset of action, short duration of action, and undergoes hepatic elimination. Myoclonus, pain at the site of the injection, post-operative nausea and vomiting are common. While common, the incidence and severity myoclonus can be reduced with pretreatment lidocaine without affecting hemodynamic stability of the patient. A rare but serious potential complication is that etomidate can also suppresses the production of cortisol and aldosterone. Ketamine – It is highly lipophilic and crosses the blood-brain barrier. It inhibits the binding of glutamine to N-Methyl-D-aspartic acid (NMDA) receptors in Thalamocortical radiations and limbic system, causing amnesia. Through the same blockade of NMDA receptor, ketamine is also effective as a painkiller. The dosage is 1 to 2 mg/kg, usually given at 100 mg. Ketamine is metabolized by liver and excreted through kidneys. The drug lessen the reuptake of the catecholamine, increases heart rate, blood pressure, and cardiac output, thus suitable for those with hypotension. However, it can worsen the cardiac depression and hypotension for those with depletion of catecholamines. Thus, maximum dose of 1.5 mg/kg is need for this situation. For those with head injuries, ketamine does not appear to increase intracranial pressure, while able to maintain the mean arterial pressure. Ketamine also relieves bronchospasm by relaxing bronchiolar smooth muscles. However, it increases oral secretions during intubation. Ketamine