The quantitative analysis of some of the non-steroidal anti-inflammatory drugs (NSAID) including: paracetamol (Acetaminophen), Acetylsalicylic acid (Aspirin), Caffeine and / or combination of either two or all the three drugs have been done using titrimetric, potentiometric and UV /Visible spectroscopic techniques. The estimation of Paracetamol, Acetylsalicylic acid, and Caffeine drugs percentage in some commercial dosage tablets was done using these methods. The concentration of a species in solution can be determined by qualitative and quantitative analysis. Various methods are adopted. This research paper mainly focuses on quantitative analysis of some selected drugs by titrimetric, UV/visible spectroscopy and potentiometric methods.