Raman spectroscopy has demonstrated a significant potential as real-time drug analysis method for pharmaceutical manufacturing processes due to its molecular specificity and fast data acquisition rate. The objective of this study was to use Raman spectroscopy as a quality control method to detect the active pharmaceutical ingredient and evaluate its uniformity in metformin 500 mg tablets by analyzing the drug through blister. Raman spectra were obtained from a dispersible Raman spectrometer (830 nm and 300 mW excitation) coupled to a Raman probe. Four spectra of each tablet were collected in triplicate using a 30 s integration time and the average spectra of the triplicates samples were analyzed. Raman spectroscopy successfully identified the active pharmaceutical ingredient in both analyzed drugs by measuring through the blister. All Raman spectra presented peaks in height and width that were similar to metformin when compared to the literature.