Is drinking monster energy once every 2-3 weeks good for you or will it cause any harm to my body ?

Energy drinks: Energy drinks have no nutritional value - meaning they're empty calories. However, there's no evidence i know of that says having one every 2-3 weeks will cause significant or lasting harm to the body. Only risk is that every 2-3 weeks becomes every 1-2 weeks, then that becomes a few times a week, then boom... You're hooked on caffeine.

Not good: Energy drinks, like monster, are not good for you in any way. They may not do any serious permanent harm but why take the risk.