What are the tests for phlebitis?

Ultrasound, PE: Phlebitis can occur in a superficial vein, and physical examination will reveal redness, pain, cord-like feel, swelling, and heat. The deep veins are examined with an ultrasound, and the presentation of DVT varies from mild pain like a muscle strain to more severe pain, swelling, and difficulty in walking.

Ultrasound: Phlebitis is an inflamed vein. The problem is that the inflammation is often caused by a thrombus (clot) and the only way to know that a clot is present or not is to have an ultrasound. So, as dr. Isobe said, the thing that needs to be done is an ultrasound.