Is A Wrist IV Hard Knot With Soreness Near The Vein Normal?

My husband was in the hospital for MRSA and had IV in his wrist where they gave him Antibiotics, he is home now but now there is a hard knot just below the IV site .It feels to be 1/2 inch or a little less running down the vein. Very sore. Is this normal? What can we do for it?