Aspirin or antihistamines may also be used to alleviate moderate, localized reactions. However, it is wise to avoid swimming in waters infested with jellyfish or other poisonous sea animals. Do not touch it with your bare hand or skin. Even when detached from the main organism, this tentacle can sting you. Seek medical attention immediately.
Jellyfish stings are most serious when they are numerous, or involve the very young or very old.
Thoroughly wash the injury and apply rubbing alcohol or vinegar several times, being careful not to touch the sting area with an unprotected hand. Apply a thick coat of baking soda paste, which may be shaved or scraped off after 30 minutes, at which time vinegar or rubbing alcohol is reapplied. Other remedies that can be applied include diluted household ammonia, lemon juice, and salt water. Immerse wound in hot water as you transport victim to the nearest hospital emergency room. The two most common poisonous spiders in the United States are the female black widow and brown recluse.