Bed Bug Bite Symptoms

What Do Bed Bug Bites Look Like?

Bed bug bite marks are discernable in some, but not all people. Those that do display bed bug bites side effects show typical allergic reactions with a wide degree of severity and appearance.

Bed Bug Bites Side Effects


Bed bug bites are typically red and itchy with localized swelling or welts.  Depending upon your body’s reaction to the bedbug bite – the area may be very itchy or a mild irritation.  These marks generally fade in anywhere from a few hours to a few days.  Some individuals, show no bed bug bite symptoms whatsoever—no itching, no redness, no swelling.  Not everyone reacts to a bed bug bite immediately upon being bit and some never react.  Those that do react, vary in the time of the response from a few hours to several days or longer.  The degree of their reaction may also produce a wide range of redness, itchiness and swelling that lasts for a few hours or several days or longer.  Caution:   excessive scratching may lead to a secondary infection.  To avoid contamination, apply a soothing non-itching salve or take an oral antihistamine.

Look at the bed bug bite photo above.  Sometimes they are in a straight line, other times, in small clusters or groups.  The straight line may be the result of the bed bug feeding as it travels forward.  Or, it may be the result of how the body was exposed while lying on the mattress – making the unprotected skin accessible.  A third explanation relates to the bedbugs’ response to motion.  As you twitch in your sleep, the bed bug stops feeding, waits for you to settle down, then moves ahead to find a new area to nibble.  The number of bites may or may not relate to the number of bugs, as one bed bug may account for several bites, or—more than one bed bug is feeding at the same time.  A situation we hope does not apply in your case.

Bed Bug Bite Marks


Check out this bed bug bite picture.  Do you see bed bug bite marks?  There are four red, raised areas, but there is no bed bug ‘bite’ mark.  Bed bugs do not have a ‘mouth’ with which to bite.  Rather, they have two tubes, one to administer an anaesthetic to numb the skin, and the second to withdraw their blood meal. 

In review, bed bug bite symptoms may:

  • be itchy, ranging from mild to strong,
  • be localized swelling or welts,
  • appear in a straight line or in clusters,
  • fade within hours, days or months,
  • be a delayed response of a few hours or up to 14 days, or
  • not be discernible, because not everyone exhibits any or all of the above bedbug bite symptoms.

This means, it is not possible—by bites alone—to determine whether you have a bed bug problem.  These symptoms could also result from an allergic reaction to soap, wool, food or any number of agents or result from another pest, e.g. mosquitos, spiders, or even mites.

What Do I Do Now?

To Ease Your Symptoms

  • Apply a non-itching salve to sooth your bed bug bite symptoms and avoid a secondary infection, e.g. a skin lotion with hydrocortisone and/or
  • Use an oral antihistamine, e.g. diphenhydramine (Benadryl) should relieve the symptoms

What Should I Not Do?

  • To avoid secondary infection, do not scratch.   If you already have an infection, consult your doctor immediately.
  • Do not discard bedding, mattresses or furniture based upon bite marks or their side effects. Review Signs of Bed Bugs:  How to Tell If You Have Bed Bugs for further details.