Hidden Dangers of Chronic Heating Pad Use!

I absolutely detest “click-bait” titles, but this one is really important for those of us who live on a heating pad to manage our pain. So please do read on.

Recently I found some dark lines on my back which had a branched pattern — like veins on a leaf. There were no other symptoms except a slight bit of a burning sensation in the area. However, much of the skin on my back, arms and chest is tender and sore all the time anyway, so I didn’t think much of it.

Turns out, it is most likely a relatively rare condition called Erythema ab igne (EAI), also known as hot water bottle rash or toasted skin syndrome. (Sounds appetizing, eh?) “Erythema” refers to the “redness” of the skin in the area that is due to chronic and prolonged heat exposure (“igne”: fire). This is how this condition starts off, and typically goes unnoticed, until the reticulate (fishnet-like) patterns of hyperpigmentation appear.

Erythema ab igne (Image from Medscape)

EAI occurs at temperatures that will not burn the skin (~43-47 degrees C) but can cause damage to the skin and the blood vessels immediately underneath it. Historically, it was seen among older people who would sit close to a fire, or among workers exposed to heat on a daily basis (e.g. metalworkers, bakers, etc.). Nowadays, it is mostly seen among  chronic pain patients who repeatedly use heating pads for long periods of time. It is also often seen more in women than men, which I felt is worth mentioning because fibromyalgia also affects more women than men.

The only treatment option is to remove the source of heat immediately. And that is paramount, because while EAI is benign at first, if the offending heat source is not removed, it can progress over time to skin cancer! Just like chronic exposure to UV radiation can result in skin cancer, so can chronic exposure to infrared radiation (more commonly known as heat!).

Lay off the heating pad-1

The logic makes perfect sense, yet it feels like a nasty surprise nonetheless! I have been depending on my heating pad to be able to sit comfortably for some 3 years now. When I extolled its virtues for pain relief, I never knew it was damaging my skin (potentially irreversibly, depending on how far it has progressed).

Needless to say, this news did not make me happy. It feels critically unfair that one of the core pillars in my fibro management scheme is now being taken away from me. It feels like somebody’s idea of a very unfunny joke.

I also want to mention that there is another condition, called livedo reticularis, that looks similar to EAI, but may indicate more serious underlying disorders, such as lupus. But LR seems to typically show up as reddish fishnet-like pattern on the legs (and does not correspond with a patient history of heating pad use). Distinguishing between the two is very important, because one of the treatments for LR is application of heat to the affected area — the one thing you must avoid if it is EAI!

Livedo reticularis (Image from MedicineNet.com)

If you see such marks on your skin, please have it checked out by a doctor, preferably a dermatologist as many primary care physicians are not even aware of EAI. This happened at a really bad time for me, because I need to change my GP with a change in health insurance. (Isn’t healthcare in America a dream?!) I am hoping the next doctor (whom I am yet to find) will take me as seriously and treat me with as much compassion as the last one, and have me properly checked out by relevant specialists.

The bottomline of this post is, if you suffer from chronic pain and heat is a major source of relief, please be judicious when using a heating pad or hot water bottle. There are hidden dangers associated with their chronic use, like the development of EAI, that I had no idea about! I am not sure I can completely give them up yet, but I am definitely cutting back on their use. It does make sitting at work very uncomfortable, but I am horrified by the potential of these lesions turning malignant. If you depend on the heating pad as much as I do, I do hope you will be careful about how long you use it for, so you don’t entirely lose your source of relief in the long run due to EAI.