Fiber optic sensors are performing a significant functionof the field of sensors. This is due to unprompted response andfacilityduringtreatment. The proposeduseoptisystem software to study the characterization ofmedical drugs by use important type of modulation was called intensity modulated fiber optic sensors. In the work, I have been using of parabolic index Multimode fiber operated on650nm. A small portion of cladding has been taken awayin the middle of the fiber opticand the core stay isuncovered in directing liquid of differentrefractiveindicesof four medicals drugssolutions, for example Pro final, Tallinn-D, Actifed and Ercѐfuryl 4%. Thetwoterminationsof the fiber are contactedwith a spatial visualizerto read the mode of medicaldrugsbefore and after sensor. The  refractive index of directive liquid  varies from  sample name liquids and the total output powersmaximum Q. Factorhas been studied.