This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anaesthesia, Subject name: Pharmacology
Which of the following is an advantage of adding adrenaline to lignocaine for local anesthetic injection? 
Select and explain. 
A. Decreases the systemic toxicity, B. Higher doses can be given, C. Duration of action can be prolonged, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Adrenaline can be added to the LA to Prolong its duration of action To decrease the risk of systemic side effects More dose of LA can be given Lignocaine with adrenaline SHOULD NOT be used for: Areas with end aeries e.g. for ring block of fingers, toes, penis, pinna (absolute contraindication) When an inhalational agent especially halothane which sensitizes myocardium to adrenaline is used. Myocardial ischemic patients Hypehyroid patient Severe hypeensives Intravenous regional anaesthesia (Bier's block)