A syringe retaining apparatus may include a syringe having a barrel with a main portion and a transition portion, and a needle extending from the transition portion of the barrel. The apparatus may include a protective cap removably mounted on the syringe and configured to receive the needle of the syringe and at least a portion of the transition portion of the barrel of the syringe. The protective cap may have an open proximal end and a closed distal end, and an interior surface and an exterior surface. The apparatus may have a locking structure configured to permit removal of the protective cap from the syringe when the syringe is inserted to a first depth insertion into the cap and resist removal of the protective cap from the syringe when the syringe is inserted into the protective cap to a second depth of insertion.
