Abstract Pigmented lesions of the oral mucosa are encountered on a routine basis in clinical practice. Oral health-care providers must assess several parameters associated with pigmented lesions. Oral mucosal color changes can be significant and gives diagnostic value of local or systemic disease though it requires clinical experience and thorough evaluation. Color changes in the oral mucosa can be attributed to the deposition of either endogenous or exogenous pigments as a result of various mucosal diseases. The various pigmentations can be in the form of blue/purple vascular lesions, brown melanotic lesions, brown heme‑ associated lesions, gray/black pigmentations. Therefore, watchful examination of all the oral mucosa is frequently required. There are variable manifestation of oral pigmentation. The specific shade, extent, site, spreading of lesion gives diagnostic importance. Interactions between the dentist and the patient's medical specialist are very important to provide a definitive diagnosis as it increase the possibility to recognize these forms of lesions. Further and more work will be done to clarify the pathogenesis and to improve the diagnosis of the disease. The historical and current scientific history and the comprehensive research on the use of patients' medications have played a vital role. Such pigmentations can be caused by both systemic and topical drugs. Interactions between the dentist and the patient's medical specialist are very important to provide a definitive diagnosis as it increase the possibility to recognize these forms of lesions.