Purpose: A new multivariate chemometric approach was developed for fast and economic compatibility determinations of ranitidine hydrochloride (as model drug) with certain pharmaceutical; polymers (Alginate & Chitosan), excipient (Lactose) and intravenous fluids (Dextrose, Ringer & Dextrose/ Ringer). Binary mixtures of the drug and each item were prepared and investigated by chemometric- assisted UV- spectrophotometry as well as by HPLC reference method. Methods: Five drug concentration levels (0.004-0.025mg/ml) of test-mixtures were used and the average drug recovery percent after two and seven days of storage from initial concentration was determined. Physico-chemical techniques including DSC, XRD, & FTIR were also performed to investigate the nature of the observed drug-additive interactions. Results: UV-chemometric and HPLC results showed that ranitidine stability in mixture aqueous solutions appears to be concentration dependent. The ranitidine content remained greater than 90% in alginate & chitosan test mixtures at all used drug concentrations (0.004-0.025mg/ml), while in lactose, dextrose, ringer & dextrose/ringer test mixtures fell below 90% at low drug concentrations (0.004- 0.009mg/ml), which suggests more ranitidine compatibility with alginate & chitosan rather than the other additives. Conclusion: The developed chemometric method, employing UV absorbance data successfully used as simple, rapid, and economic alternative tool in drug-additive compatibility determinations.