Why do spider bites itch

Spider bite: what to do if you've been bitten by a spider

One of the consequences of climate change is that you can no longer simply go back to business after a spider bite. Nurse's thorn fingers, water spiders, house spiders and other poisonous species from distant regions have found a new home in this country thanks to milder temperatures. If the eight-legged insects feel cornered inside or outside, they will bite you. The confrontation is usually mild and not a cause for panic if you are familiar with the correct course of action. This guide explains what to do if you've been bitten by a spider.



Experiencing a spider bite in real-time is the exception. Spiders consider humans a danger and avoid direct contact as much as possible. This does not prevent the insects from colonizing our apartments and houses as cultural successors.

Here, of course, spiders live in secret and search for food at night. Since spiders do not compete with humans for food, they hunt prey. Only when the long-legged fellows feel cornered do they bite.

This is often the case when working in the garden, at a picnic in the forest or by water, or when you lie down on the uninvited bed neighbor while sleeping. As a result, a spider bite is only based on it certain symptoms makes noticeable:

  • slight swelling
  • Redness around the bite wound
  • itching
  • Burn

At first glance, symptoms resemble a mosquito bite after a spider bite. However, were you the first recently immigrated species of spider bitten, kick more severe complaints on, comparable to a bee or wasp sting. Do you suffer from inexplicable Headache, nausea, vomiting, dizziness or even palpitations, please go without hesitation to the family doctor.

Tip: Spiders provide valuable protection in the fight against pests in the house and garden. Experts have calculated that the spider population in Germany annually devours more than 5 tons of insects. Among other things, lice and mites of all kinds are at the top of their menu.

Catch a spider

With more than 46,000 species of spiders worldwide, you can't be sure which spider left you with the bite wound. It helps if you have the opportunity to capture the culprit for identification.

Thats is quite easy:

  • Required material: glass and a piece of cardboard / sturdy paper
  • Put the glass over the spider
  • Slowly push the paper under the opening
  • Rotate glass

If it is necessary to see a doctor, take the vicious prisoner with you. A doctor can use more effective treatments by knowing the species of spider. Please let the spider live. In most cases it is a native, harmless species that has only defended itself and should not be sentenced to death.

Unless you manage to capture the long-legged culprit, you should get one take a picture. Alternatively quickly write down the main features, like size or color. Every detail is useful for the most precise identification possible.


The effects are tolerable if you get a spider bite treat promptly. A combination of Home remedies and preparations in your medicine cabinet prevents the wound from becoming infected. How to act rightif you were bitten by a spider:

  • Important: do not scratch, even if it itches a lot
  • Rinse the bite wound with clean water
  • ideally disinfect with iodine
  • Cooling with ice as a cooling pad from the freezer compartment or ice cubes in a bag

When the swelling subsides, it relieves Itch-relieving ointment the irresistible urge to scratch yourself. And you should definitely not scratch yourself, because inflammation and infection are inevitable in this way. Make sure no improvement within 30 to 60 minutes of the complaints, please consult your family doctor.

Children and allergy sufferers to the doctor

If children and allergy sufferers are affected by a spider bite, we recommend the Immediate consultation with a pediatrician or family doctor. In both cases, the health consequences for a weakened immune system should not be underestimated. In this case, only a doctor can give the all-clear. Take the immediate measures recommended here beforehand by cooling and disinfecting the bite wound to relieve the acute itching.

Tip: If you are bitten by a spider abroad, please do not waste time with self-treatment. Contact a doctor or hospital straight away. Above all outside of Europe there are different species of spiders whose bite can be fatal.

Fatal misdiagnosis

Spider bites are rare and usually not a cause for concern. In fact, the number of serious poison spider bites advertised in the tabloids far exceeds the number of actual bite wounds. Inflammatory skin areas of unclear origin are often prematurely declared as a spider bite, although other diseases are more obvious and a spider bite could not be observed.

Regularly misdiagnosed as a spider bite wound, infections in staph, streptococci, herpes, Lyme disease, shingles, and some variants of skin cancer. Such a misdiagnosis can have fatal consequences, because it lulls the person concerned into apparent security.

It is highly recommended that a diagnosis be critically examined if the biting spider has not been observed or captured. This is especially true in the event that the symptoms do not improve within a short period of time, but rather the symptoms worsen.

Poisonous spiders in Germany

It is not possible to identify a spider based on the bite wound. The exact diagnosis and the resulting treatment methods are only possible if the species of spider in question is known. So that you are prepared for an emergency and can call the culprit by name, we provide you with the following most important venomous spiders in Germany in front:

Thorn finger, nurse thorn finger (Cheiracanthium punctorium)

The spider species is now at home in Central Europe in the course of global warming. In addition to the water spider, Dornfinger is the only species whose bite is accompanied by noticeably painful and medically relevant sequelae. Since nurse's thorn fingers avoid human dwellings and are nocturnal, bite injuries are highly unlikely.

Distinguishing features are:

  • Body: up to 15 mm long, oval shaped
  • Coloring: front part of the body red-orange, abdomen yellowish-green
  • special features: black poisonous claws, noticeably long legs

Water spider, silver spider (Argyroneta aquatica)

The second poisonous spider species native to Central Europe lives hidden in clear lakes between aquatic plants. There is seldom a confrontation with people and the resulting bite wounds. Usually anglers and swimmers are affected. If the water spider gets into distress, it bites, which causes symptoms similar to those of a wasp sting

Distinguishing features are:

  • Body: 8 to 15 mm long
  • Color: forelegs yellow-beige to brownish, abdomen silvery and shiny
  • special characteristics: elongated body shape with long legs

Garden spider (Araneus diadematus)

Among the diverse species of cross spiders, an encounter with the garden cross spider is the most likely. The widespread species of spider likes to stay in orchards, bushes and tree tops. Here it spins its webs to hunt insects as their preferred prey. If it cannot escape in time when it encounters people, the garden spider uses its biting tools. It can only penetrate the human epidermis in the thinnest areas of skin. The sequelae are uncomfortable and painful, but usually not harmful to health.

Typical distinguishing features are:

  • Body: 10 to 18 mm long
  • Color: gray-brown with light or dark cross-shaped spots
  • special characteristics: hairy legs, females with a markedly enlarged abdomen