An apparatus for performing phlebotomy through a peripheral intravenous line. The apparatus includes an introducer and a catheter configured to advance the catheter through a peripheral intravenous line. A y-adapter with a port of larger diameter is configured to receive the catheter and place in fluid communication with the peripheral intravenous line. When advanced the catheter is configured to transport a bodily fluid (i.e. blood) to a volume outside of the body.