In this thesis, we will lay out some of the most common oral issues related to drug administration, including xerostomia, gingival hyperplasia, oral ulceration, taste disorders, burning mouth syndrome, black hairy tongue, oral candidiasis, alveolar osteitis, angioedema, dental discoloration and osteonecrosis of the jaw. Some complications can either be a cause of a certain medication or it could be the symptom of an underlying systemic disease.