This study compared the effects of two different kinds of intravenous catheter material, polypropylene (plastic) and fluoroethylenepropylene (teflon), on the early onset and incidence of phlebitis. Cannula type was randomly assigned to participating subjects. Each insertion site was observed six and 24 hours after initiation of the treatment conduction. Forty-four subjects completed the study. The findings indicated that utilizing intravenous catheters made of teflon, rather than plastic, would reduce the incidence and early onset of phlebitis.