Green & Poison — toxic plants and mushrooms (including the death cap), why folk tests fail, and when to go to hospital now.
Islands & Body — heat, floods/landslides, tsunami, dengue, leptospirosis, melioidosis, and reef caution.
Field Protocols — the do-and-don't matrix, antivenom/hyperbaric, beach flags, and the rule to call 1669 when life is at risk.
Want numbers and a printable card? See Field Reference. Want the citations? See Deep Dives. Want to learn from reported incidents? See Field Notes.
Critical:Box jellyfish — rinse with vinegar (4–6%) liberally for ≥30 s, remove tentacles with tweezers (not bare fingers), seek medical care for severe reactions. Do NOT use fresh water, urine, alcohol or rub. Bluebottles / Physalia — hot water at ~45 °C for ~20 min is the evidence-based approach; vinegar is not indicated. For elapid neurotoxic bites use pressure-immobilisation; for most viper bites immobilise at heart level and get to hospital/antivenom. For unknown mushrooms with delayed symptoms or onset >5 h — go to hospital ASAP (call 1367 / 1422).
Sea & Shore
Phuket's west coast sees seasonal box jellyfish presence in places; postings change year to year. Unposted does not mean safe. Follow red and purple advisories, speak to a lifeguard if present, and keep small children in shallow, guarded areas. The west coast (Kata, Karon, Patong, Surin, Nai Harn) takes the full southwest monsoon swell from May to October, which is when rip currents run hardest.
“Portuguese man o' war (Physalia physalis)” by Marco Zanqueta — CC BY 2.0 · Wikimedia Commons
License: CC BY 2.0. First-aid differs from box jelly — hot water ~45 °C for ~20 min, no vinegar.
Rip currents: if caught, don't fight straight back — swim parallel to shore until out of the narrow current, then angle in. Float and wave for help if exhausted.
Venomous fish: stonefish are well-camouflaged in reef and shallow rock; shuffle feet in murky shallows where advised.
Sea snakes: usually not aggressive, but never handle them.
Blue-ringed octopus: small, reclusive, deadly neurotoxin — do not touch.
Undergrowth
Most antivenom-treated snakebites in Thailand are Malayan pit vipers. Watch where you put hands and feet in leaf litter, especially at dusk. Macaques are wild — do not feed, do not snatch food, and secure bags. Monkey bites must be taken seriously (rabies and B-virus): wash with soap and water for 15 minutes and seek PEP assessment immediately.
“Asian elephant in Khao Phra Thaeo National Park, Phuket” by Khaosaming — CC BY-SA 2.0 · Wikimedia Commons
License: CC BY-SA 2.0. Give elephants a very wide berth — never approach a cow with a calf.
Snakes: stay still if unsure, back away slowly, don't try to kill or handle.
Elephants: give a very wide berth on trails and roads; never approach a cow with a calf.
Slow loris: protected and venomous — illegal to touch or photograph for money.
Scorpions and leeches: check boots and gear after wet scrub.
Green & Poison
Rule 1: if you didn't buy it from a known edible source, don't eat wild mushrooms or unknown plants. Folk tests (silver spoon, boiling with onion) are not reliable. Some deadly species look like edible ones. If ingestion is suspected or symptoms are delayed (>5 h) — go to hospital now. Keep a sample or photo and note the time eaten if safe to do so.
Poison Control: Ramathibodi 1367
DDC (Department of Disease Control):1422
Sea mango (Cerbera odollam): extremely toxic — never chew or eat.
Dumb cane (Dieffenbachia): irritant and caustic — keep away from children.
Islands & Body
Most drowning deaths are rip currents. Heat exhaustion and heat stroke are real. Phuket has experienced landslides after heavy rain — avoid steep, freshly saturated slopes. Tsunami evacuation routes and towers exist; pay attention to warnings. Dengue is year-round — use repellent, cover up at dawn and dusk, and avoid aspirin and ibuprofen if febrile until dengue is ruled out.
“Aedes aegypti” by James Gathany, CDC — Public Domain · Wikimedia Commons
Public Domain (CDC). Dengue is year-round in Phuket — use repellent, cover up at dawn and dusk, and avoid aspirin or ibuprofen if febrile until dengue is ruled out.
Heat: hydrate, avoid midday exertion, watch for confusion and dry skin (heat stroke is an emergency).
Floods and landslides: never cross flooded roads or rivers; avoid slopes during and after intense rain.
Dengue, leptospirosis, melioidosis: prevention is key — cover, repel, and avoid wading in floodwater with open cuts where possible.
Field Protocols
When in doubt, call 1669 and go to hospital. This is harm-reduction, not a substitute for professional care. Ossuary Atelier is not medical staff.
“Phuket, Thailand: Warning flag at Mai Khao Beach” by CEphoto, Uwe Aranas — CC BY-SA 4.0 · Wikimedia Commons
License: CC BY-SA 4.0. Always follow the flag posted on the day — systems vary slightly between beaches.
Marine envenomation: follow the correct first-aid for the specific organism (vinegar vs hot water). Don't delay transfer for severe symptoms.
Snakebite: keep calm and still, immobilise the limb, remove tight jewellery, don't cut, suck or tourniquet.
Animal bite or scratch: wash soap and water for 15 minutes, cover, seek PEP assessment the same day.
Suspected poisoning: call 1367 or 1422, don't induce vomiting blindly, go to the ER.
When is jellyfish season in Phuket? May to October (southwest monsoon), especially July to September. Check DMCR marine warnings.
Box jellyfish sting? Vinegar (4 to 6 percent) for 30 seconds or more, remove tentacles with tweezers. Don't use fresh water, urine, alcohol or rub. Call 1669 if severe.
Rip current at Kata, Karon or Patong? Don't swim straight back — swim parallel to shore until out, then angle in. Float and wave for help if exhausted.
Monkey bite? Wash with soap and water for 15 minutes, seek PEP assessment the same day. Don't feed macaques.
Disclaimer: This guide is for practical harm-reduction and education only. It is not medical advice. Follow local authorities, lifeguards, and medical professionals. Ossuary Atelier is not medical staff.