Objective: We investigated the incidence of side effects related to contrast medium employed in our hospital based on monitoring materials to improve the safety of contrast-enhanced examinations.  Furthermore, we compared the incidence of side effects between the original product and generic drugs to confirm the safety of each preparation.
Methods: The survey period was from April 2007 until March 2011.  Based on the number of patients who underwent contrast-enhanced examinations and that of patients with side effects, we calculated the incidence of side effects in our hospital, and confirmed its annual changes.  Subsequently, we again collected the incidence of side effects per each manufacturer’s preparation employed, and confirmed the state of side effects of individual preparations.  Furthermore, we evaluated the symptoms as side effects, interval until appearance, and treatment for side effects during the data collection period, as well as the subsequent state, symptoms as side effects, and interval until appearance.  The chi square independence test was employed to compare the results among groups.  p<0.05 was regarded as significant (paired test).
Results: There were no changes in the annual incidence of side effects.  There were also no significant differences in the annual incidence of side effects among the preparations.  Furthermore, there were no marked differences in the symptoms, interval until appearance, treatment for side effects, or subsequent state among the preparations.
Conclusion: We investigated the appearance of side effects regarding contrast-enhanced examinations for 4 years.  We confirmed that there were no differences in the incidence of side effects among the preparations.

Objective: The use of generic drugs is promoted for the purpose of reductions of medical costs and patient’s copayment.  In general, it is thought that clinical effects of the original brand and the generic drugs are equal if they are bioequivalent.  However, it is necessary to inspect their therapeutic equivalence to use the generic drugs securely.  We, therefore, assessed the therapeutic equivalence and pharmacoeconomics by substitution of an original drug (Amaryl®) with a generic drug (Glimepiride [Tanabe]).
Methods: Therapeutic Equivalence: The total variation was calculated by using the HbA1c levels before it switched from Amaryl® to Glimepiride [Tanabe].  The tolerance limits were set as 1/4 of the total variation.  Pharmacoeconomics: The difference of drug prices and the difference of patient’s copayment were calculated.
Results: As the variation of HbA1c levels was within tolerance limits before and after switching from Amaryl® to Glimepiride [Tanabe], we evaluated that their therapeutic effect was equivalent.  The difference of drug prices after switching from the original to the generic one was 4,582.6 yen/year on average (minimum: 949.0 yen, maximum: 12,045.0 yen); the difference of patient’s copayment was 872.5 yen/year on average (minimum: 0 yen, maximum: 3,613.5 yen).  These data show that the use of the generic drugs is effective to reduce medical costs.
Conclusion: For further promoting the use of the generic drugs, we consider it essential to compare the therapeutic equivalence and the safety of the original and the generic drugs in clinical practice.