Purplish discolouration of toes is by no means a common problem, but rarely is it an overly serious medical condition. In most cases, discoloured toes can be treated once the specific cause is determined.
When the foot's blood flow is interrupted, the toes can become discoloured. Within this overall cause, several specific factors may be the primary cause for the blood flow disruption.
As explained by the Podiatry Network, ischemic foot is a leading factor behind the overall cause of blood flow restriction. With ischemic foot, blood circulation is limited because of arterial damage to the foot, blood clots or cholesterol deposits.
Purple discolouration in the toes can occur from trauma. Bruising restricts blood flow, resulting in discolouration. Provided the toe is not broken, the bruising will heal on its own as long as you keep excess weight off the toe.
According to the Internet Journal of Anesthesiology, warfarin can cause purple discolouration of the toes. Warfarin is an anticoagulant, so it typically increases blood flow. However, in rare occurrences the medication has restricted foot circulation.
Cold weather decreases blood flow, so discolouration is a natural side effect of frostbite. Unlike other purple discolouration of toes, this discolouration may not go away over time. In severe cases, the toe tissue dies and requires amputation.