In the literature, there is little evidence that higher rifampicin dosage is associated with higher frequency of adverse effects. Depending on the nature of the toxicity, one could say that hypersensitivity could be independent from dosage, when digestive disorders may be related. Plasmatic concentrations studies have not given strong arguments to link higher rifampicin dosages with side effects occurrence rates. After oral absorption, plasmatic peak occurs after two to five hours and varies among individuals but also in the same patient overtime. This particular pharmacokinetic profile could explain discrepancy in adverse events (AEs) frequencies.