Ask the Doctor: How do I treat a jellyfish sting?

Q: How do I treat a jellyfish sting?


A: Now that it’s hot and beach season is here, there’s nothing as refreshing as frolicking in the ocean and jumping the waves. But we may encounter more than just people in the shallow water.


jellyfish 300x225 Ask the Doctor: How do I treat a jellyfish sting? Photo

Do you know how to treat a jellyfish sting?

Jellyfish are free-swimming marine animals with a gelatinous bell and long tentacles covered with toxin-filled sacs. They can be found in every ocean and sea.

Unfortunately because jellyfish are translucent, the first time we may know of their presence is when we feel the sharp pain of the sting from swimming into them or stepping on one!



Initial effects:

  • Stinging pain
  • Itch
  • Rash
  • Raised welts

Progressive reactions:

  • GI symptoms (abdominal pain, diarrhea, nausea, vomiting)
  • Lymph node enlargement
  • Muscle spasms
  • Numbness and tingling

Severe reactions:

  • Breathing difficulty
  • Coma



The majority of jellyfish stings can be treated with simple home remedies.

Action steps to take:

  • Remove any tentacles clinging to the skin with a stick or tweezers. Wear gloves if they are accessible. 
  • Soak the affected area or rinse with acetic acid (vinegar) for 15-30 minutes to prevent the sacs (nematocysts) from releasing the toxin.
  • Scrape the edge of a credit card or cardboard over the affected skin to remove any adherent sacs. Then apply vinegar again.
  • Rinse eye stings with a commercially prepared saline solution (e.g. Artificial Tears) Dab around the eyes with a vinegar-soaked towel.
  • For mouth stings, gargle with a mixture of one-quarter cup vinegar with three-quarters water. Do not swallow the mixture.
  • Take an over-the-counter analgesic for pain
  • Can take Benadryl for itch.



  • If there is no vinegar available, rinse with seawater or alcohol.
  • Apply a paste of baking soda with vinegar or shaving cream to keep the nematocysts from releasing toxins during removal with the card.
  • Do not:
    • Rub the area
    • Compress with ice
    • Soak with fresh water

These actions can hasten the release of toxin from the sacs.


When to Pursue Medical Treatment/Assessment

Get immediate medical care if:

  • Chest pain, difficulty breathing
  • Difficulty swallowing
  • Swelling of the lips or tongue
  • Involves very old or very young person
  • If the sting involves an extensive area, face, or genitals


Treatment by medical personnel for redness and swelling of the skin (sign of cellulitis) or prolonged symptoms may include:

  • Pain Medication
  • Topical Steroids
  • Antibiotics (if cellulitis present)


Severe reactions must be tended to immediately with:

  • Resuscitation (CPR) if there is a sudden loss of heartbeats.
  • Pain medication injections may be necessary.
  • Epinephrine injection for anaphylaxis (shock)



  • Don’t pick up dead jellyfish from the beach. It may still have nematocysts with toxins
  • Don’t swim in jellyfish-infested areas. Even if wearing wetsuits, the tentacles can get trapped under the collar.
  • Carry a first aid kit with you when away from home. (This is VITAL advice if travelling with children). Keep oral antihistamines in the kit for emergency use.


Knowing how to take care of emergencies and being prepared affords you peace of mind. Get information about the state of the water from beach staff, lifeguards or local news. If the conditions are good, go out and enjoy yourself!