A hot spoon won't cure your mosquito bite, but it can burn you

A hot spoon is a home remedy that circulates every summer. The method is simple. You heat a metal spoon in hot water, press it against the bite, and wait for the itch to fade. Some people say it works. The real question is whether it works for the reason they think, and whether it is safe.

What the hot-spoon idea claims

Supporters of the trick say heat breaks down the proteins in mosquito saliva, and that this switches off the itch at its source. It is a tidy explanation. It is not what the evidence points to.

When a mosquito bites, she injects saliva as she feeds. Your immune system reacts to it, and that reaction shows up as the itch and the raised lump (NHS, insect bites and stings). The study credits the effect to heat-sensitive nerve receptors, not to the saliva proteins (Müller et al., 2011).

What heat actually does to a bite

A single-arm cohort study of 146 volunteers tested a device that delivers concentrated heat to the skin. The device caps its temperature at 51°C and applies it for three or six seconds, timed by a microchip. Participants reported less swelling, less pain and less itch, usually within ten minutes, and pain relief was the strongest effect (Müller et al., 2011).

The study was small, it was not randomised, and most participants had wasp stings rather than mosquito bites. It supports controlled heat for bites and stings. It says nothing about a spoon.

The device limits both temperature and time. A spoon dipped in hot water has neither control. Its temperature depends on the water, the metal and how long you wait.

The burn risk

A metal spoon carries dry heat straight to the skin, the kind of contact the NHS lists as a common cause of burns. If you do burn yourself, hold the burn under cool running water for 20 minutes, as soon as you can. Do not put creams, oils or butter on it (NHS, burns and scalds).

What to do instead

The reliable options are old and unglamorous, and the NHS sets them out plainly. For a swollen bite, put an ice pack wrapped in a cloth on it for at least 20 minutes. A clean cloth soaked in cold water works too. Keep the area raised if you can, and take paracetamol or ibuprofen if it is painful (NHS, insect bites and stings).

For the itch, use antihistamines or a hydrocortisone cream to reduce itching and swelling. The most useful instruction is also the hardest. Do not scratch the bite, because broken skin can become infected. The NHS also advises against home remedies such as bicarbonate of soda (NHS, insect bites and stings).

See a pharmacist if the skin around the bite feels hot, looks red, or becomes painful or swollen, or if it produces pus. See a GP if a child under one year old is bitten or stung. Ask for urgent help if symptoms get worse instead of better, or if you were stung in the mouth, throat or near the eyes. Call 999 for signs of a serious allergic reaction. These include swelling of the lips, mouth or throat, or difficulty breathing (NHS, insect bites and stings).

Preventing the bite

The best bite to treat is the bite you never get. The US EPA puts physical barriers first. Cover gaps in walls, doors and windows, keep screens in good working order, and cover baby carriers and beds with netting (US EPA). Cover exposed skin with long sleeves, long trousers and socks.

For the skin that stays exposed, use a repellent and follow label directions and precautions closely. A repellent supports the barrier. It does not replace it.

What we know

Sources cited

1. NHS, Insect bites and stings. https://www.nhs.uk/conditions/insect-bites-and-stings/
2. NHS, Burns and scalds. https://www.nhs.uk/conditions/burns-and-scalds/
3. Müller et al., Clinical, Cosmetic and Investigational Dermatology, 2011. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3257884/
4. US EPA, Tips to prevent mosquito bites. https://www.epa.gov/insect-repellents/tips-prevent-mosquito-bites