This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous system, Subject name: Pharmacology
Drugs that can be used in opioid de-addiction are? 
Select and explain. 
A. Clonidine, B. Diazepam, C. Methadone, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: All of the drugs can be used. Methadone is effective orally, more potent ,longer acting and prevents withdrawal symptoms because it is slowly released from tissues. Clonidine a central alpha 2agonist can suppress autonomic.if withdrawal symptoms such as nausea, vomiting, anxiety and diarrhea. Night time sedation with a hypnotic like diazepam is helpful. Ref KD Tripathi 8th ed