This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hypeension, Arrhythmias, Dyslipidemia, Subject name: Pharmacology
Which of the following drugs should be given in sustained release oral dosage form? 
Select and explain. 
A. An anti-arrhythmic drug with a plasma half life of 10 seconds used for acute treatment of PSVT, B. An anti-inflammatory drug with a plasma half life of 24 hr, C. A hypnotic drug with a plasma half life of 2 hours, D. An antihypeensive with a plasma half life of 3 hours
D: An antihypeensive with a plasma half life of 3 hours
Answer: D: An antihypeensive with a plasma half life of 3 hours 
Explanation: Sustained release preparation are used for prolonged duration of action of drug . So, used when drug has sho half life and when we require the action of drug for longer duration. Anti-hypeensive drug are used for lifelong. So, sustained release preparations are required. Anti-arrhythmic drugs used in treatment of PSVT are not to be used as sustained release preparation as we need action for only a sho duration. Anti-inflammatory drug with the half life of 24 hrs is already acting for long duration we don't need sustained release preparation. Hypnotic drug with a half life of 2hrs will work for 5-6 hrs. So, no need of sustained release preparation.