Present study investigates the serum levels of trace elements, immunoglobulins and vitamin C in drug addict patients before and after clinical intervention. In this study 10 ml of blood was collected from each of the drug abuse patients during admission and after 1 month of treatment and from each of the control subjects. Samples were then analyzed for determining the serum level of trace elements (Cu, Zn, Fe & Mg), immunoglobulins (IgG, IgA & IgM) & Vitamin C using atomic absorption spectroscopy, turbidimetry method and UV-spectroscopic method respectively. A higher serum Cu level (1.099±0.235 mg/L) in drug abusers than the control group (0.914±0.128 mg/L) was found. The decreased serum Fe level (0.980±0.232 mg/L) of drug abuser was increased to 1.029±0.225 mg/L after intervention. The increased serum Mg level (19.922 mg/L) of drug abusers was decreased to 19.237 mg/L after intervention. The serum concentrations of IgA (252.374±62.262 mg/dl) and IgM (149.935±57.617 mg/dl) were found higher in drug abuser patients than the control group. The concentration of vitamin C was decreased after treatment from 0.527±0.208 mg/dl to 0.510±0.318 mg/dl which was not significant.