Differential scanning calorimetry(DSC) was used as a screening technique for assessing the compatibility of some drugs with excipients. On the basis of DSC results, interaction of ibuprofen with PVP K40 was found and eutectic formations with PEG 6000 or magnesium stearate were demonstrated. Fenoprofen Ca was found to interact with PEG 6000. Naproxen showed interactions with PEG 6000, PVP K40, PVPP and Mg stearate. Interactions of tiaprofenic acid with PVP K40 or PVPP were found and eutectic formations with PEG 6000 or Mg stearate were observed. Bisoprolol hemifumarate, metoprolol tartrate and penbutolol sulfate were found to interact with lactose.