Thrombophlebitis, or phlebitis for short, refers to the inflammation of the vein. Depending on the location of the lesion, phlebitis can be divided into superficial phlebitis and deep phlebitis. The pathological changes include intimal hyperplasia of blood vessels, narrowing of the lumen, and slow blood flow. The surrounding skin may show congestive erythema, sometimes accompanied by edema. Gradually, these symptoms subside, with congestion being replaced by pigmentation, turning the erythema into a brownish color.
A small number of patients may experience reactions.