A catheter enclosure device for locking an intravenous catheter therein with tamper-evident features to deter unauthorized use. The catheter enclosure device may be particularly useful for peripherally inserted central catheters (PICC). The enclosure device comprises an open-top box and a removable lid for covering the box. The open-top box has a compartment for holding the proximal end of an intravenous catheter. The lid comprises a panel for covering the open portion of the open-top box and a folding wing that overhangs the forward end of the box when covering the box. The folding wing further comprises a retaining anchor. When the folding wing is folded down, the retaining anchor inserts into a locking slot on the forward end of the box, thereby preventing the lid from being removed off the box. Also disclosed are methods for using the catheter enclosure device.