Objectives: Analysis of the literature on drug-induced aphthous ulcers and mucosal ulcerations and evidence-based grading., Material and Methods: Four literature sources were analyzed. Three groups of key words were used: 1) oral, buccal, genital, mucosal; 2) ulcer, ulceration, aphthous, aphthosis; 3) induced, drug, adverse-effects, with cross-overs. Four grading patterns were used: presence of aphthous term or synonym, typical clinical description of aphthous ulcer, presentation suggesting diagnosis of aphthous ulcer, criteria defining likelihood of drug causality., Results: We examined 66 of the 220 publications responding to our selection criteria. Typical clinical description of aphthous ulcer and/or clinical presentation suggesting the diagnosis of aphthous ulcer were noted for 8 compounds with likely or palausible patterns of causality. For 21 compounds, we found only aphthous term or synonym without a clinical description or presentation., Discussion: Our review of the literature individualized a group of 8 compounds where the diagnosis of aphthous ulcers was plausible and another group of 21 compounds where the diagnosis of aphthous ulcers requires confirmation. The clinical relevance and limitations of this analysis are discussed., Conclusion: Drug-induced aphthosis is probably a real phenomenon. Causality of the 8 compounds in the first group is simply more fully documented than for the 21 compounds in the second group. A low evidence level may not confirm these hypotheses. Some drugs may have been incorrectly ruled out due to lack of information.