Jellyfish sting in Puerto Rico: what to do, including man o' war stings
For a jellyfish sting in Puerto Rico, rinse the area with plenty of household vinegar for at least 30 seconds; if you have no vinegar, wash it with seawater. Don't rub it with sand, press or scrape it. Then soak the area in hot tap water, 107 °F to 115 °F, for 20 to 40 minutes. Get help right away if pain increases or you have trouble breathing.
Can we help by telehealth? Sometimes: it depends on the evaluation.
Is this an emergency?
This is not an emergency service. Call 911 or go to the nearest emergency room if you have:
- Trouble breathing
- Chest pain or changes in pulse
- Fainting or collapse
- Pain that keeps getting worse
- Belly pain, cramps or strong muscle spasms after a sting
Help lines:
- 911 — Emergencies
- 1-800-981-0023 — Línea PAS (mental-health crisis line)
- 988 — Suicide & Crisis Lifeline
- 1-800-222-1222 — Poison Help
First aid for a jellyfish sting in Puerto Rico
These are the steps from MedlinePlus, published by the U.S. National Library of Medicine:
- Rinse the sting site with large amounts of household vinegar for at least 30 seconds. According to MedlinePlus, vinegar rapidly stops the thousands of tiny stinging cells that have not yet fired.
- If vinegar is not available, wash the sting site with ocean water.
- Then soak the area in hot tap water at 107 °F to 115 °F (42 °C to 46 °C), not scalding, for 20 to 40 minutes.
- Afterwards you can apply an antihistamine or steroid cream, such as cortisone cream.
What not to do
MedlinePlus says to protect the affected area and not rub sand on it, apply pressure or scrape the sting site. Don't use remedies that aren't in these instructions. If you are unsure, call Poison Help at 1-800-222-1222, which also serves Puerto Rico.
Portuguese man o' war stings in Puerto Rico
The Portuguese man o' war looks like a jellyfish, but according to NOAA it is a siphonophore, a close relative. You can recognize its balloon-like float, which may be blue, violet or pink, and its long tentacles, which average about 30 feet.
It lives mostly in tropical and subtropical seas. Its sting is rarely deadly, but it is very painful and causes welts. It can still sting weeks after washing ashore, so don't touch any you see on the sand, and teach children not to touch them.
MedlinePlus gives the same first aid for all types of jellyfish.
Symptoms of a more serious reaction
Most stings cause pain, burning and welts on the skin. According to MedlinePlus, a Portuguese man-of-war sting can also cause belly pain, changes in pulse, chest pain, chills, headache, muscle pain and spasms, numbness, sweating and, in severe cases, collapse.
MedlinePlus says to get medical attention right away if pain increases or there are any signs of breathing difficulty or chest pain. In that case, call 911. See also emergencies.
Jellyfish stings in children
Children get the same first aid. Test the hot water with your own hand before soaking your child's skin, so you don't scald them. If your child has any of the serious-reaction signs on this page, call 911. For questions about symptoms or creams, call Poison Help at 1-800-222-1222.
Can we help by telehealth?
Sometimes. In an online doctor visit the doctor can look at the area, check for signs of infection in the days after the sting and advise on relief for itching and pain. If appropriate, the doctor can prescribe medication. We do not prescribe controlled substances.
If you have any sign of a serious reaction, don't book a video visit: call 911 or go to the ER. See ER vs urgent care in San Juan.
Before you go to the beach
Check the National Weather Service San Juan beach forecast, which reports rip current risk and the UV index, and follow the flags and lifeguards. There are area guides for beaches such as Isla Verde and Condado. On vacation? See also sick on vacation in Puerto Rico.
Video visit: US$79 · Pay by card · See the price and what is included
Before you book
- You must be physically in Puerto Rico during the visit (visitors and tourists are welcome).
- We see patients from 6 months old. Patients under 21: a parent or legal guardian must be on camera for the whole visit.
- Real-time video only; we do not do phone-call visits.
- We do not prescribe controlled substances.
Frequently asked questions
- What should I do right after a jellyfish sting?
- Rinse with plenty of vinegar for at least 30 seconds (or seawater if you have no vinegar), then soak the area in hot tap water at 107 °F to 115 °F for 20 to 40 minutes. Don't rub it with sand.
- Can a man o' war on the beach still sting?
- Yes. According to NOAA, it can sting even weeks after washing ashore. Don't touch it.
- When should I go to the ER for a sting?
- If pain keeps getting worse, or you have trouble breathing, chest pain, changes in pulse or you faint. Call 911.
Sources
- Jellyfish stings (MedlinePlus, U.S. National Library of Medicine) (accessed 2026-09-30)
- What is a Portuguese man o' war? (NOAA) (accessed 2026-09-30)
- Beach forecast, San Juan (National Weather Service) (accessed 2026-09-30)