**Abstract**

Identification of a new drug molecule to a new target, specifically viral, bacterial, and fungal infection, is the prime focus of time immortal. The tridiagonal practice of drug discovery for emerging viral infection turned out to be a new venture to combat the morbidly and mortality of recent pandemics due to viral, bacterial, fungal, infection and infestation, the emerging number of viral infections day by day, the targeted therapy with the gap in assessment lead to reprofiling or repositioning available FDAapproved formulation give promising drug candidate for various infection specifically the current scenario of antiviral drug-reprofiling through drug designing approach, the emergence of resistance to existing antiviral drugs and re-emerging viral infections are the greatest challenges in antiviral drug discovery. The reprofiling approach is a worthy strategy to get the potent antiviral in brief span of time to overcome the challenges in antiviral therapy. The present chapter will be another representing the most promising results of reprofiling (Repositioning or repurposing) approach in the treatment of various infectious diseases.

**Keywords:** antiviral, drug-resistance, re-emerging, viral infection, fungal infection, bacterial infection
