Now a days problem in health has become common. So, instead of curing them, prevention through dietary supplements has proven to be useful. In the case of patients who have already developed the disease atleast relieving pain and suffer is a challenging thing. In this context L- arginine is doing better compared to other essential aminoacids up to some extent. Arginine was found to reduce the pain associated with pulmonary hypertension foun to be associated with sickle cell anaemia. It also reduces the reperfusion injury after ischemia, trauma and shock. Some of the drugs with L-arginine as component are under clinical trials and hope to be available in the market soon. Severe preeclampsia is characterised by headaches, blurred vision, and inability to have high photovision, nausea and vomiting. L-Arginine along with Vit C and E are given as medical food to the patients and decrease in condition symptoms is the project now under phase II clinical trial. However the role of arginine in ameolirating preeclampsia symptoms is uncertain except with that of hypertension. Arginine is used to treat pain in sickle cell anaemia, lung damage, reperfusion injury, Trauma and shock but should be excluded during sepsis.