Superficial thrombophlebitis refers to inflammation (phlebitis) and thrombosis in subcutaneous veins. It is most commonly caused by intravenous cannulation of veins but may also be due to hypercoagulable states, stasis within varices, visceral cancer, and infection (usually due to Staphylococcus aureus, then termed septic thrombophlebitis). Ten to twenty percent of cases are associated with occult deep venous thrombosis (DVT). Superficial thrombophlebitis presents as erythema and induration of a superficial vein. There may be a low-grade fever. Complications include extension to the deep venous system and sepsis or endocarditis in cases of septic thrombophlebitis.

Trousseau syndrome is recurrent migratory thrombophlebitis associated with visceral cancer (usually pancreatic).

Superficial thrombophlebitis can often be distinguished from cellulitis on the basis of history (recent intravenous catheter site) and physical exam (palpable induration or cord in the area of a vein).

Superficial thrombophlebitis on the chest with enlarged veins is sometimes called Mondor disease.