What can cause red swollen toes?

Several: Certain condition can cause this such as raynaulds phenomenum. This is a benign condition of spasms of the venous/end arterioles of the digits. Cold and stress and smoking are triggers.

Many possibilities: Some causes of swelling can include systemic problems such as hypertension, and problems with the kidneys and localized issues such as arthritis, infection, lymphatic obstruction, blood clots, varicose veins, trauma (fracture, sprain, tendonitis, tight shoes) and side effects to medication. Have it evaluated by a professional and get the appropriate treatment.