Chronic kidney disease is a progressive disease which has become a real public health issue. In patients with renal disease, drugs pharmacokinetics may be altered. The handling of drugs requires a special attention in these patients. Indeed, there is a risk of accumulation and drug overdose if dosage is not adjusted to the stage of renal insufficiency. Thus, to achieve a dosage adjustment knowing how to evaluate renal function is absolutely necessary. Different formulae are available including the Cockcroft and Gault formula aMDRD and CKD-EPI. In patients with cardiac issues, it appears that the CKD-EPI formula is that of choice in terms of clinical risk stratification. However, some summaries of product characteristics (SmPC) of drugs used in cardiology, such as Dabigatran(®), mention the need to use the Cockcroft-Gault, less accurate than aMDRD and CKD-EPI, in order to adjust the dose in patients with impaired renal function. Standardization of recommendations is necessary to limit disparities in dosage and drug exposure according to the formula. SmPCs however, are not the only source of information to obtain data on the use of drugs in the renal insufficient population. Some other information sources exist, reliable, updated and easily accessible.