Diabetic foot red spots: causes, checks and when to act
Red or discoloured spots on a diabetic foot are not always an emergency, but they should never be ignored. Diabetes can reduce sensation and slow healing, so a small mark can become a serious problem if it is missed.
Why red spots appear
A red spot can be a pressure mark from footwear, a tiny blister, a friction injury, an insect bite, or the first sign of inflammation. In people with diabetes, poor circulation and neuropathy mean the skin may not send normal pain signals, so visual and temperature checks become the main early-warning system.
What to check at home
- Press the spot gently. If it blanches (turns pale) and then returns to red, blood flow is present. If it does not blanch, seek same-day advice.
- Compare temperature. Use the back of your hand or a handheld thermometer to check the same area on the other foot. A warm red spot can signal inflammation.
- Look for breaks in the skin. Any blister, crack or open area needs careful cleaning and professional review.
- Check your footwear. A new red spot often lines up with a seam, strap or tight area in a shoe.
When to contact a clinic
Call your podiatry clinic, GP or diabetes nurse the same day if the red spot is warm, swollen, painful, not blanching, or has any break in the skin. Seek emergency care for spreading redness, fever, pus, black or blue discolouration, or an open wound.
How PodiaScan helps
PodiaScan records temperature across seven zones on each foot — six on the sole and one on the top of the foot — and flags left-right differences. A warm red spot matched by a temperature rise is a stronger warning sign than colour alone, prompting earlier review.