A warm pad on a crampy, gassy stomach feels good, and for ordinary indigestion or period-related cramping it’s fine. But belly pain is the one place where heat can cause real harm, because some of the things that cause it need surgery, not comfort.
Don’t use heat on unexplained tummy pain
Two reasons:
- It hides the picture. Doctors work out what’s wrong partly from where the pain is and how it changes. Heat dulls the signal and can delay you going in.
- It increases blood flow. With inflammation or infection in the abdomen, that isn’t what you want. The same reasoning applies to fresh injuries.
If you don’t know why your stomach hurts, and it’s more than mild, skip the pad and get it checked.
Go to A&E if…
- Pain started around your belly button and moved to the lower right, with nausea, loss of appetite or fever. That’s the classic appendicitis pattern.
- Your belly is rigid, and any movement or pressing makes it much worse
- Severe pain with fever, vomiting that won’t stop, or you can’t pass stool or wind
- Blood in your vomit or stool, or black tarry stools
- Sudden severe pain in a woman who could be pregnant, or with a late period
- Tearing pain in the tummy or back, especially if you’re older, smoke or have high blood pressure
- Pain with chest pressure, breathlessness or sweating. Call 995.
Pain in the side or back rather than the front has its own list of causes: lower back pain on the left side.
When a warm pad is reasonable
For familiar, mild discomfort that you’ve had before and understand:
- Period cramps. Heat has decent evidence here. See heating pad for period cramps and period cramps: what actually helps.
- Trapped wind and bloating after a heavy meal.
- IBS cramping, if that’s a diagnosis you already have.
- Mild indigestion that settles within a few hours.
- Endometriosis pain, where it’s already been diagnosed and you know the pattern.
Use the lowest setting with the cover on, lying on your back with the pad resting on your belly, for 15–20 minutes. Never lie face down on the pad.
Why heat eases gas and cramping
Our gut is a muscular tube.
When it cramps, that’s muscle contracting. Warmth relaxes the abdominal wall and, along with the nerve effect that dulls pain signals, makes cramping less uncomfortable.
We always recommend whenever possible, to stand up more, go for gentle walking…cos gentle walking often helps more, because movement shifts trapped wind.
Never on a pregnant belly
Keep heat pads off the abdomen in pregnancy. Heat on the lower back or shoulders on a low setting is generally fine for pregnancy aches, but check with your doctor or midwife. Any tummy pain in pregnancy needs medical review, not a heat pad. See heat pads in pregnancy and pregnancy back pain.
Also avoid heat if…
- You’ve had recent abdominal surgery and the wound isn’t fully healed. See heat after surgery.
- You have a fever
- You have reduced sensation over the abdomen, including from diabetes
Full list: who should not use a heating pad.
One more thing
Using a heat pad on your belly every day for weeks is a sign in itself. It can cause a lasting net-patterned skin stain (see toasted skin syndrome), and more importantly it means you have pain that nobody has explained. Get that looked at.
The heat pad we use
We’ve supplied the Bremed BD7800 since 2010. It holds a steady temperature, covers a whole lower back and has a machine-washable cotton cover. Physiotherapy clinics in Singapore use it with their patients.
Clinically reviewed by: Nigel Chua (Hand Occupational Therapist) & Louise Yow (Physiotherapist). This article is general information, not a diagnosis. electricheatpad.com sells electric heat pads.
