Bites may look like small, flat or raised areas that can become inflamed, itchy, red, or blistered. Bed bug bite reactions don’t always appear immediately after you’re bitten and symptoms may take a few days to be noticeable. However, not everyone reacts to bed bug bites in the same manner. Bed bug bites are often grouped together in a small area and at times may occur in a line or a zigzag pattern.

Bed bug bites are not always painful and can go unnoticed for hours or days. This allows bed bugs to withdraw human blood for up to 10 minutes with each feeding. Bed bug bites occur most commonly on exposed skin, such as the upper body, neck, arms, and shoulders.

Bed bug bites, for some, can develop into itchy, red welts or swelling the day after being bitten. However, bites may not become obvious for a while or at all on some individuals. Many bites leave no mark and go completely unnoticed.

If you develop a rash after being bitten by a bed bug, avoid scratching the affected area. If the rash persists or becomes infected, contact a medical professional immediately.