A jellyfish's tentacles are loaded with small bee-like stingers that contain a toxin used to stun small water prey. This is why within 4-24 hours after a human is exposed to the stinger of a jellyfish, the affected skin can become painful, red and swollen, and an itchy rash can appear.
With severe stings — when a lot of venom is injected into the skin or when a person is extremely allergic to the venom — weakness, dizziness, nausea, headache, muscle aches, spasms and difficulty breathing can result.
If severe symptoms occur, call your doctor or go directly to the emergency room.
First aid for mild symptoms
If symptoms are mild, the following first aid advice may help:
- Remove any tentacles that are still present on the skin.
- Do not remove with a bare hand — touching the tentacles with bare skin will only cause more area of exposure and pain.
- To remove the tentacles, use tweezers, or a flat-edged, non-sharp object (such as the edge of a credit card, hotel room key or non-cutting side of a butter knife) in a sweeping, downward movement.
- Use salt water for rinsing.
- Once tentacles are removed, place the exposed limb or body region in hot water (immersion is best, shower is acceptable). It is recommended that the water be “as hot as can be tolerated” for 20 minutes.
- Hot water is used to deactivate the proteins in the jellyfish venom.
- Ice packs have not been shown to be helpful in pain control, but may be used for comfort and swelling after hot water immersion is complete.
- Oral pain medications, such as acetaminophen or ibuprofen, may help to decrease discomfort.
Call the Poison Control Center at 1-800-222-1222 if you have any questions.