Do i need rest after taking medications because most of the times i become sleepy once i had taken the medicines?it had affected my work.

Check with doctor: I am not sure which medications you are taking because many medications can cause drowsiness as a side effect. I suggest you talk to your doctor if this is affecting your ability to work. Be careful with driving and do not operative heavy machinery until your doctor has had a chance to adjust your dose or find an alternative medication that wouldn't make you so drowsy.