X-ray is an ionizing-radiation and it has been used in many processes due to the developing technology. For security purposes, X-ray instruments are been using at the entrance of the airports, shopping centers, etc. In this study, potential effects of X-ray were investigated on five different types of drugs: analgesics (acetaminophen, acetylsalicylic acid, naproxen, flurbiprofen), proton pump inhibitors (lansoprazole, pantoprazole sodium sesquihydrate), anti-diabetics (metformin HCl, pioglitazone), heart failure drugs (verapamil HCl, spironolactone) and anti-hypertensives (losartan, clopidogrel hydrogen sulphate) by several different methods. In our previous study these drugs were analyzed by ESR before and after X-ray irradiation (0,24; 1,2; 58 mGy). According to the ESR results, acetylsalicylic acid tablets were affected after 58 mGy irradiation due to coated polymer (HPMC). In conclusion, these drugs were investigated before and after 0,24; 1,2 and 58 mGy X-ray irradiation by UV-spectrophotometry, dissolution test, SEM, FT-IR, DSC/TGA in this article. As a result of this study, X-ray did not cause a significant effect on drugs generally. Only a few significant differences were detected by different studies (for metformin HCl by DSC/TGA, for acetylsalicylic acid by dissolution test, and for acetaminophen and acetylsalicylic acid by UV spectrophotometry were detected significantly difference before and after irradiation).