Adverse drug reaction (ADR) is an unwanted, undesirable effect of medication resulting in mild to severe effect on the patient. This review explains definitions of ADR and it differentiation with adverse drug event, medication error. ADRs may cause increased length of stay or initial reason for admission and are major cause of morbidity and mortality worldwide. Risk factors for ADR occurrence include age, gender, patients with multiple diseases and multiple drug therapy (polypharmacy). ADRs are classified into different types based on the mechanism and onset of reaction. The causal relation between suspected drug and reaction can be assessed by using causality assessment scales. The severity and preventability of ADR can be assessed by severity assessment scale and preventability scale respectively. Clinical Pharmacists play an important role in monitoring and management of ADRs.

INTRODUCTIONDM and HTN are most common and serious diseases with chronic complications and these both are risk factors for cardiovascular diseases which increases the risk of stroke, myocardial infarction, heart failure, and chronic kidney disease.1,2 The main objective of this study is to find out prevalence of both HTN and DM in hospitalized patients along with comparison of age and gender. Up to 75% of adults with diabetes also have HTN, and patients with HTN alone show insulin resistance. 3,4 ABSTRACT Background:The study aimed to assess the prevalence of Hypertension (HTN), Diabetes mellitus(DM) and other diseases along with comorbid conditions, disease complications and also to assess medication adherence in a tertiary hospital in Karimnagar, Telangana, India. Methods: A Cross sectional study is performed by analysing a total of 500 patient's individual case safety reports (ICSR). Prevalence of Hypertension and Diabetes along with most prescribed drugs are analysed. Medication adherence is analysed by using Morisky Medication adherence questionnaire scale (MMAS-4). Results: Patients with past history of DM, HTN and other diseases which was found to be 245 (49%) patients. Patients with highest disease prevalence were found to be with HTN (56.73%), DM (31.83%) followed by other diseases like asthma (8.57%), Cerebrovascular accident (4.89%) etc., Total of 66 Patients were ruled out with comorbid diseases. Patients with HTN+DM (47) were found to be highest followed by DM+HTN+CVA (4). MMAS-4 revealed 208 patients were using medication out of 245 patients with previous history. According to MMAS-4 most of the patients were with medium adherence (76). Prevalent drug used for HTN include Amlodipine and for DM Telmisartan+Hydrochlorthiazide. Conclusions: The study revealed that almost half of the admitted patients were with HTN and DM. The patients were counselled properly to adhere strictly to the prescription. Medication adherence to HTN and DM was found to be good in this study. Since the disease complications were also ruled out, the health care professionals are recommended to spread awareness on DM and HTN and disease management in order to control disease and improve health outcomes.