- Petechiae – tiny pinpoint red or purple spots caused by small amounts of bleeding under the skin.
- Purpura – larger reddish-purple patches that may appear when blood leaks from small vessels.
Because many different conditions can produce similar-looking symptoms, appearance alone is rarely enough to identify the exact cause.
Possible Causes of Red or Purple Spots on the Legs
1. Minor Irritation or Allergic Reactions
Some rashes develop after exposure to allergens, medications, plants, chemicals, or insect bites. These reactions may cause redness, itching, or scattered spots that improve once the trigger is removed.
2. Viral or Bacterial Infections
Certain infections can trigger widespread skin changes. In some cases, red or purple spots appear alongside symptoms such as:
- Fever
- Fatigue
- Headache
- Body aches
- Swollen lymph nodes
Doctors generally recommend prompt evaluation if a rash appears together with signs of infection.