Chesapeake Bay Sea Nettles

• Immediate burning or stinging the moment a tentacle brushes the skin.
• Red, raised welts in the shape of the tentacle - often long, curved, or whip-like lines.
• Itching and a prickly, hot sensation that builds over 10–20 minutes.
• Mild swelling around the welts; sometimes small blisters along the line of contact.
• Discomfort that usually fades within a few hours; faint marks may linger a day or two.

1. 1Get out of the water calmly - thrashing breaks tentacles and spreads stinging cells.
2. 2Rinse the area generously with seawater (not fresh water) to wash off remaining tentacles.
3. 3Carefully remove visible tentacles with a gloved hand, tweezers, or the edge of a credit card. Don't rub with bare hands.
4. 4Apply a vinegar (5% acetic acid) rinse for 30 seconds to neutralize stinging cells, then rinse again with seawater.
5. 5Soak the area in hot water (about 110–113°F / 43–45°C) for 20–40 minutes to ease pain.
6. 6After the soak, apply 1% hydrocortisone or calamine for itch; an oral antihistamine helps if welts persist.

• Don't rinse with fresh tap water right away - it can trigger more stinging cells to fire.
• Don't rub with sand or a towel - both rupture remaining stinging cells.
• Don't use urine. It doesn't work and can make things worse.
• Don't apply ice directly to the sting before the hot-water soak - heat is more effective for sea nettle pain.
• Don't pop blisters; cover them loosely if they form.

Most sea nettle stings can be managed at home. Get help quickly for stings to the eyes or mouth, very large welts, signs of infection, or a child or older adult who looks unwell after a sting. Call 911 for trouble breathing, swelling of lips or throat, chest pain, weakness, or a stung person who feels faint - rare but possible allergic reactions to jellyfish stings can be serious.

• Check the Maryland DNR Sea Nettle Forecast and local beach reports before swimming.
• Swim early in the season (June) or after heavy rain that drops Bay salinity - sea nettles prefer warm, salty water.
• Wear a rash guard, dive skin, or stinger suit in known nettle zones; even thin fabric blocks most stings.
• Apply a sting-protective lotion (sting-no-more or jellyfish-safe sunscreen) before entering the water.
• Stay clear of visible jellyfish - broken-off tentacles still sting for hours.
• On boats, watch where you handle anchor lines, crab pots, and trotlines - tentacles wrap around gear.

• Jellyfish stings - first aid- Mayo Clinic
• Marine envenomation guidelines- Wilderness Medical Society
• Sea nettle forecast and biology- NOAA Chesapeake Bay Office
• Bay sea nettle conditions- Maryland DNR
• Beach safety and stinging organisms- Virginia Marine Resources Commission
• Treatment of jellyfish stings- American Red Cross