Spider bites: symptoms and treatment
Depending on the spider and its victim, spider bites can cause anything from mild itching and redness to an allergic reaction (such as anaphylaxis) that becomes a medical emergency and could even result in death. Although there have been no reported deaths in South Africa in recent decades due to spider bites, the venom can cause pain and discomfort.
There are two types of spider venom:
- Cytotoxic venom has a localised action, so it only affects the site of the bite.
- Neurotoxic venom affects the nervous system.
“Cytotoxic venom causes skin tissue on the bite site to decay, while neurotoxic venom can cause cramping followed by weakness of the skeletal muscles,” explains ER24 Emergency Care Practitioner Sam Daniel.
The most dangerous spiders in South Africa are the neurotoxic black and brown button (or widow) spiders, while sac spiders and violin spiders are cytotoxic. Baboon and rain spiders might bite if threatened but aren’t poisonous. However, even if you’re bitten by a non-poisonous spider, it’s best to get a tetanus shot.
Neurotoxic bite symptoms: seek urgent help
- Immediate, burning pain that quickly spreads to the lymph nodes
- Intense muscular pain and cramps develop within an hour, followed by anxiety and sweating
- Rigid muscles
- Racing pulse
- Involuntary twitching
- Flushed face.
Call ER24 on 084 124 for real help, real fast – or get the victim to the closest emergency room, where antivenom may be administered if required. Other treatments might also be necessary. Even if you didn’t see the spider that bit you, always seek medical help immediately if there’s a possibility the bite could have been from a venomous spider and/or you’re having a reaction.
“Never attempt to self-medicate a spider bite,” warns Daniel. “Go to your closest emergency room, if possible, with a photo of the spider. This helps doctors determine what medication and other treatments to administer.”
Cytotoxic bites: symptoms and self-treatment
Spider bites often occur at night when the spider is disturbed by a sleeping person. The bites are often painless, so the victim might not even be aware of being bitten. However, fang marks, bleeding and redness may be a sign. Although there may be some swelling and itchiness at the bite site, it’s not too obvious at first. However, within 12-24 hours, it becomes painful, swollen and red. After a couple of days, the lesion might form a cluster of blisters.
Treatment is usually based on your symptoms and focuses on preventing and treating secondary infections and complications. Most patients will recover from a cytotoxic spider bite without medical assistance. Here’s what you can do at home:
- Wash the bite area with cool soapy water to clean the wound and help prevent infection.
- Apply a cool compress, such as an ice pack, to ease the pain of the bite and reduce swelling.
- Elevate the bite site, if possible, to help reduce inflammation and swelling.
- Take painkillers for minor pain.
- Monitor the bite, and if necessary, especially if surrounding redness spreads or worsens, seek medical care.
Reference:
GJ Muller et al, Spider bite in Southern Africa: Diagnosis and treatment, Continuing Medical Education, Vol 30, no10, 2012
C E du Plessis, Venomous spider bites in South Africa: epidemiology and clinical features, 2019
