Snake bites in Thailand: first aid, antivenom and what not to do

Snakes in Thailand

Thailand is home to a range of venomous snakes, including cobras, kraits and vipers. Most bites happen in rural areas, to farm workers and to people walking at night, but bites also occur in gardens, on hiking trails and occasionally in towns. Many bites, even from venomous species, inject little or no venom, but there is no reliable way for a bystander to tell, so every bite needs hospital assessment.

Venoms broadly act in two ways. Neurotoxic venoms, typical of cobras and kraits, can cause drooping eyelids, difficulty swallowing and speaking, and progressive weakness that may affect breathing. Haemotoxic venoms, typical of vipers, interfere with blood clotting and can cause bleeding, as well as painful swelling around the bite. Symptoms may be delayed for several hours, which is another reason not to wait.

First aid: what to do

Move away from the snake to avoid a second bite. Call 1669 straight away and arrange the fastest safe transport to a hospital. Keep the person as still and calm as possible, because movement can speed the spread of venom through the lymphatic system.

Immobilise the bitten limb, for example with a splint or sling, and keep the person lying down or sitting still; carry them if you can rather than letting them walk. Remove rings, watches, bracelets, anklets and tight clothing near the bite before swelling starts. If they vomit, lie them on their side. If they stop breathing normally, start CPR if you can and follow the 1669 call handler's instructions; snakebite paralysis can affect breathing while the heart is still beating, and hospitals can support breathing with a ventilator.

Whether a firmer pressure bandage should be used depends on the type of snake and is a decision for trained responders; follow the 1669 call handler's advice rather than improvising.

This guide summarises published public-health guidance. It is not a substitute for first-aid training or for the instructions of the 1669 call handler or a doctor; if in doubt, call 1669.

What not to do

Many traditional first-aid measures cause harm and delay treatment. The WHO South-East Asia guidelines on snakebite management advise against them. Do not cut or incise the bite, try to suck out the venom, apply a tight tourniquet or ligature, pack the bite in ice, apply electric shocks, or put herbs, chemicals or other substances on the wound. Tight tourniquets can cut off blood supply and cost a limb.

Do not give alcohol or painkillers such as aspirin or ibuprofen, which can worsen bleeding. Do not try to catch or kill the snake: that risks more bites. If it can be done safely, a photograph from a distance can help the hospital, but doctors in Thailand generally identify the type of envenoming from the symptoms and blood tests, and treatment does not depend on bringing the snake.

In hospital: antivenom

The WHO describes high-quality snake antivenoms as the most effective treatment for preventing or reversing most of the harmful effects of snakebite envenoming. Antivenom is not given to everyone bitten; doctors observe the patient, check blood clotting and look for signs of paralysis, then decide whether antivenom is needed and which one. Expect to be kept under observation for at least a day, even if you feel well, because symptoms can be delayed.

Thailand has a long history of antivenom production. The Queen Saovabha Memorial Institute of the Thai Red Cross Society, known to visitors as the Bangkok Snake Farm, was founded in 1923 as the country's first antivenom production centre and makes antivenoms from the venom of local snakes, covering both neurotoxic and haemotoxic species. It is a WHO Collaborating Centre. Hospitals across Thailand keep antivenom, but smaller facilities may need to transfer patients or obtain supplies, which is why calling 1669 early matters.

Reducing the risk

Wear closed shoes and long trousers when walking through long grass, in plantations or on forest trails, and use a torch at night. Do not put hands into holes, under rocks or into piles of wood or leaves. Give any snake you see a wide berth and do not try to handle it, even if it appears dead.

If you are staying in a rural area for a long time, find out where the nearest hospital with an emergency department is and how you would get there at night.

Frequently asked questions

Sources

1. World Health Organization — Snakebite envenoming fact sheet
2. WHO Regional Office for South-East Asia — Guidelines for the management of snakebites, 2nd edition (2016)
3. WHO Thailand — Integrating science, education and public health: the Bangkok Snake Farm (2023)
4. Thai Red Cross Society — Queen Saovabha Memorial Institute
5. WHO South-East Asia — National Institute for Emergency Medicine (institute details)
6. GOV.UK — Thailand travel advice: Getting help