How Long Does Bed Bug Bite Take To Show Up (And Why)?

Exact Answer: A Day To Two

A bed bug is a small insect that feeds on the blood of both humans and animals. In addition to their dependence on humans and animals for food, they also depend on them for transport as though they are insects they do not have wings.

Bed bugs do not measure more than a centimetre. They range from 1 to 7 millimetres mostly and are reddish-brown. Their body shape is oval and flat.

A bed bug bite is not harmful. However, it makes one feel itchy and thus, uncomfortable. At most, they can cause some allergic reactions.


How Long Does Bed Bug Bite Take To Show Up?

Stage After Bed Bug BiteTime Taken
Visibility of bite1 to 2 days
Itching bite wounds2 to 4 days
Healing of wounds1 to 2 weeks

People tend to panic if they happen to glance at any bed bugs. These creatures are infamous for not being able to get rid of them easily. However, their bites are of more concern than their presence.

The bed bug bites are itchy and a person should immediately lookout for such bites upon discovering any bed bug notorious insects.

When a bed bug bites a person, they might not feel or even notice it at the beginning. Usually, the bed bug bites while a person is asleep. Moreover, the bite mark of the bug is small at the outset and is barely visible to the naked eye.

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The bite mark takes time to develop into a full-blown wound that would be adequately visible to any eye. It swells up and might even turn red or brownish. It would take anywhere between 1 to 2 days for the bed bug bite to show up.

As the bed bug bite would grow, it would turn problematic and uncomfortable for the person. Within two to four days of the bite, it would become itchy and risks the danger of infection if pricked.

However, the bed bug would not last for long. It is destined to wear off either by proper medication or over a prolonged period if left undisturbed. It would take a week or two for the bite to be erased.

Why Bed Bug Bite Takes That Long To Show Up?

As mentioned earlier, a bed bug is a small insect. Although it is visible to the naked eye, yet it can easily be written off or ignored when cleaning the house. One needs to take proper care in eliminating these insects.

A bed bug can bite a person without the person even noticing it. The insect feeds on human blood at night times when people are in deep sleep. People do not even feel the insect crawling upon them once they are asleep. The bug makes a small bite that, at first can only be viewed with a magnifying glass.

Moreover, the saliva of the bug contains an anesthetic. This chemical prevents the person from getting disturbed or getting awake and helps the bug feed to its heart’s content. This is one of the reasons behind the slow realization of a bed bug’s bite.

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Another reason behind this long time is the small mouth of the bug. As the small mouthparts of the bed bug bite one’s skin, since the area affected is small, the bite does not show up early.

However, as the effect of anesthetic slows and the wound spreads to the surrounding skin area, it gets swelled up. This swelling and skin redness becomes more pronounced when the mast cells release an enzyme called histamine. Such a prolonged series of actions take place within 48 hours of the bug bite.


A bed bug bite takes 24 to 48 hours to show up. When a bug bites a person, it leads to a small bite which is so small that it is invisible to the human eye. In addition to that, the insect also releases an anesthetic to the host’s body because of which the person does not feel it.

However, as the effect of the anesthetic wears off after a couple of hours, the bite mark starts to grow. It becomes red, swollen, and itchy after two days.



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Hi! I'm Nidhi.

Here at the EHL, it's all about delicious, easy recipes for casual entertaining. So come and join me at the beach, relax and enjoy the food.

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