Hot water bottle risks: burns, toasted skin syndrome and staying warm safely

Few things feel as comforting in the colder months as snuggling up with a hot water bottle. It is a fast, simple and affordable way to keep warm through winter - yet it can also result in serious harm.

In the UK, there were 5,944 burn injuries linked to hot water bottles between 2014 and 2023.

High-profile cases have highlighted the risks. In 2022, Sharon Portingale suffered third-degree burns after taking a hot water bottle to bed. In 2021, Helen Powell was scalded when the hot water bottle she was using for back pain relief split.

The risks of a hot water bottle

Burns and scalds are not the only injuries associated with using a hot water bottle.

Heat applied close to the skin - particularly for long periods, or when someone falls asleep - can damage tissue even without a sudden leak or burst. The risk increases when the heat stays concentrated on one spot.

Toasted skin syndrome (erythema ab igne)

Toasted skin syndrome is also known as erythema ab igne (redness from fire).

Regular exposure to heat sources - including hot water bottles, heat pads, space heaters and even laptops - can lead to a red, fishnet-like pattern appearing on the skin. This happens because tiny blood vessels in the skin widen as they attempt to manage the heat.

In many cases, the problem improves soon after the heat source is removed. But if exposure is prolonged and repeated, the skin can become thinner and develop hyperpigmentation, where some areas appear darker than others.

This hyperpigmentation occurs due to damage to the skin’s elastic fibres and the release of melanin from skin cells.

The damage may be permanent, although treatments such as laser therapy or topical creams containing 5-fluouracil can help.

Delayed recognition of toasted skin syndrome, alongside ongoing heat exposure, may also contribute to the development of cancers, including basal cell carcinoma, neuroendocrine carcinoma and low-grade lymphoma.

Who is more vulnerable to heat damage?

Some people are more prone to heat-related skin injury. For instance, individuals with sickle cell disease and those living with chronic pain are more likely to experience erythema ab igne or significant burn injuries.

People with diabetes who have circulatory complications that affect temperature regulation may feel colder and therefore rely on heating aids more often. However, diabetes-related circulation problems can also reduce sensation, meaning a person may not realise their skin is overheating until a burn has already occurred.

Hot water bottles should not be used to keep babies warm or to pre-warm their sleeping area. Newborns have brown fat that helps them maintain a healthy body temperature and protects them from hypothermia.

At birth, brown fat makes up about 5% of a baby’s body weight and is stored around key organs to generate heat.

Staying warm

What are the options for staying warm without a hot water bottle?

In bed, weighted blankets can help by reducing how much warm air is pushed out whenever you move beneath them. If you are sitting down, it can also help to keep your feet raised and away from the floor, which is often the coldest part of the room.

Rather than relying on one thick coat or jumper, it is worth remembering that wearing layers is much better at trapping air and retaining heat.

Your fingertips contain roughly twice as many nerve fibres as your palms and are particularly sensitive to cold.

Because of this, wearing gloves - even indoors - can reduce the need for your body to divert heat to the hands, while also helping to keep the heat your body generates close to your skin.

Getting up and moving from time to time will produce heat and help circulate warmer blood from your core to extremities such as your fingers and toes.

Safer hot water bottle use

If you do choose to use a hot water bottle, avoid filling it with boiling water and make sure you add cold water to the bottle. Ideally, the water should be around 50°C-60°C.

Finally, you can lower the likelihood of tissue damage when using hot water bottles or heat pads by spreading the heat more evenly - reposition them so warmth is not focused on one area for too long.

Adam Taylor, Professor and Director of the Clinical Anatomy Learning Centre, Lancaster University

This article is republished from The Conversation under a Creative Commons licence. Read the original article.