First aid for spider bites

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By Catherine Holland By Catherine Holland
By Catherine Holland By Catherine Holland

PHOENIX -- There are two medically significant spiders in North America -- the black widow and the brown recluse.

Almost all spiders are venomous, however, most spiders are too small, or their venom too weak, to be dangerous.

Black widow spiders are often considered the most venomous. You can identify this spider by the red hourglass marking on its belly. The bite usually feels like a pinprick. At first, slight swelling and faint red marks will appear but within hours, intense pain, stiffness, chills, fever, nausea, vomiting and severe abdominal pain will occur.

Brown recluse spiders can be deadly. Their venom is extremely poisonous, and their bite can cause serious wounds and infections. When the brown recluse bites, it is often painless, then the skin reddens, turns white, develops a red “bull’s-eye,” blisters and becomes painful.

This spider has a violin-shaped marking on its back. The bite produces a stinging, followed by localized redness and intense pain within eight hours. A blister forms at the site and then sloughs off to leave a deep, enlarging ulcer like wound.

It is sometimes difficult to determine if you’ve been bitten by a spider and can only be identified by symptoms, without any visible local bite.

Most scorpion stings do not cause serious reactions and can be treated with ice and over-the-counter pain medication. but scorpion antivenom is available if needed.

If you are bitten by a spider

  1. Cleanse the wound.
  2. Slow the venom’s spread. If the spider bite is on an arm or a leg, tie a snug bandage above the bite and elevate the limb to help slow or halt the venom’s spread. Ensure bandage is not too tight that it cuts off circulation.
  3. Use a cold cloth.
  4. Seek immediate medical attention.

Most importantly when a local reaction continues to get worse for more than 24 hours and redness is spreading away from the bite with increased pain, numbness and tingling, go to the emergency room.

Suction syringes designed to extract toxins don’t work.

Dr. Art Mollen's practice is located at 16100 N. 71st St. in Scottsdale. For more information, call 480-656-0016 or log on to