Unsaturated pyrrolizidine alkaloids are hepatotoxic, that is, damaging to the liver. PAs also cause hepatic veno-occlusive disease and liver cancer. PAs are tumorigenic. Disease associated with consumption of PAs is known as pyrrolizidine alkaloidosis.
The venom is what causes the symptoms. The main symptoms are pain, itching, swelling and redness at the sting site. Severe pain or burning at the site lasts 1 to 2 hours. Itching often follows the pain. Swelling. The bee sting may swell for 48 hours after the sting. The swelling can be small or large.
Insect Bites and Stings and Spider Bites. Insect and spider bites often cause minor swelling, redness, pain, and itching. These mild reactions are common and may last from a few hours to a few days. Home treatment is often all that is needed to relieve the symptoms of a mild reaction to common stinging or biting insects and spiders.