Many people with cancer will experience pain at some point during their illness. If you or a loved on are experiencing cancer related pain, it's important to let your oncology team know as they will be able to prescribe pain relief medication.
If you are looking to try a non-drug treatment, either instead of, or along side pain relief medication, heat therapy can be an affordable and effective solution.
What is heat therapy?
Therapeutic heating or thermotherapy has been used for many years to treat pain and reduce swelling. It is a safe treatment which has a beneficial effect on pain levels, plus there are few harms associated with its use.
Heat therapy is the practice of applying heat to the body for therapeutic benefits. Heat is primarily used for non-inflammatory body pain, relaxation, comfort & reassurance and works by applying heat to an affected area to help relieve persistent pains associated with muscle stiffness, sensitivity and cramping.
Recent studies to investigate whether heat really makes a difference in healing have been inconclusive, but there is plenty of anecdotal (and some clinical) evidence to suggest that heat therapy can probably take the edge off several kinds of pain, mostly duller and persistent pains associated with stiffness, cramping, and neuropathic sensitivity. Heat therapy can also help to loosen stiff joints and relieve achy muscles which are common side effects of cancer treatment.
How does heat therapy reduce pain?
Heat causes the blood vessels to open wide (dilate). This brings more blood into the area and when blood flow increases to a particular area of the body, it brings along oxygen and nutrients that can help to speed up the process of healing.
Heat can also help to relieve muscle tension. This is because the application of heat helps your muscles stretch by increasing tissue extensibility, causing any stiff or tense muscles to relax.
Heat is also reassuring, and reassurance can provide an analgesic effect. Most people's comfort zone is a warm place, and so, no matter what kind of pain you have, the brain is likely to interpret a safe source of warmth as good. Therefore the sensation of heat on the skin provides an analgesic effect: it alters the perception of pain so you don't hurt as much.
The presence of heat on the skin is also soothing and can ease stiffness by making the tissues more supple.
Types of heat therapy
There are 2 broad categories of heat therapy, dry heat and moist heat although there is also professional heat therapy which uses ultrasound or radiation.
Dry heat — also known as conducted heat therapy, can take the form of heating pads, heat packs, hot water bottle, electrical heating pads and saunas.
Moist heat — also known as convection heat, can take the form of moist heating packs, hot baths and steamed cloths or towels. Moist heat therapy products and services are usually preferred for penetrating deeper into the muscle tissues and achieving a higher increase in blood flow than dry heat.
While there is much debate about whether dry or moist heat is more effective, clinical studies have not noted a significant difference and it tends to come down to personal preference.
How to use heat therapy at home
Effective heat therapy products typically maintain a relatively warm – not piping hot – temperature. A few products utilise high temperatures, and are only safe when there is enough insulation between the heat source and the skin.
Dry heat can be applied at home using:
microwaveable wheat bag
gel pack that can be microwaved
single use, air-activated heat pad
an electric heating pad
a heat lamp
You can also target many different areas at once by having a warm shower or soaking in a warm bath. Or you can create your own moist heat pack by soaking a washcloth or small towel in hot water, wringing it out, folding it and applying it to the painful area.
It is important to note that if heat is applied to the skin it should not be hot; gentle warmth will be enough. If excessive heat is applied there is a risk of burns and scalds. A towel can be placed between the heat source and the skin for protection. The skin should be checked at regular intervals.
How long should I apply heat therapy for?
The duration of heat therapy depends on the type of pain you are experiencing. Sufficient time is required for the warmth to penetrate deep into the muscles. Usually, the longer the heat is applied, the more relaxed the muscles feel.
Often, minor muscle tension and stiffness can be relieved after around 15-20 minutes of applying heat therapy. If you have moderate to severe pain, you might benefit from longer sessions -between 30 minutes to two hours.
It is never recommended to sleep with a heating pad.
What pain can heat therapy treat?
Heat is often helpful for relieving the following types of pain:
muscle aches and pains
stiffness in muscles and joints
strains and sprains
old sprains or strains
pain associated with neck or back injury
aching muscles from over-exertion
aching pains from fibromyalgia and other chronic pain conditions
cramping or spasm pains such as period pains.
When you shouldn't use heat therapy
It is important to note that heat therapy is not suitable for all types of injuries and should not be applied to pain that presents alongside inflammation, swelling or bruising. If the injured area is already hot, then you will not benefit from applying heat; you should instead apply a cold pack to restrict blood flow and reduce inflammation.
Don't use heat on a fresh injury: you could increase swelling, which in some cases could increase your overall level of discomfort. In these cases, ice is a better choice.
You shouldn't apply heat to irritated skin. Skin conditions such as contact dermatitis or eczema can also be triggered by high temperatures and by low humidity, so dry heat therapy in particular can lead to flare-ups.
Don't apply heat therapy to open wounds, including incisions that are still healing - heat used on open wounds will increase blood flow to the wound and potentially increase bleeding.
Certain conditions that make the skin more sensitive, such as diabetes, may preclude heat therapy as a recommended option.
If you have had radiation therapy, don’t apply heat to your treatment sites. You should also avoid applying heat to areas where you have tumours. If you have any concerns, please speak to your oncology team before using heat therapy.
You should wait at least 4 hours before using any form of heat therapy if you have undertaken moderate to rigorous exercise.
If you have high blood pressure or any condition that affects your heart, you should always consult your doctor before undergoing any kind of heat therapy.
Consult with your healthcare team if you have questions or concerns regarding these contraindications.
Potential risks of heat therapy
There are few risks to heat therapy, but there are some potential consequences of incorrectly using heat therapy products and services:
Skin rash or burn. Prolonged use of hot packs and heating pads, or application of a heat source that is overly hot without a barrier on the skin, can cause contact burns.
Decreased blood pressure. Even after a single session of heat therapy, blood pressure will drop. Due to the sudden decrease in blood pressure, individuals who often experience dizziness or light-headedness upon standing) may find certain heat treatments problematic.
Increased heart rate. The heart has to work at a faster pace to keep up with the increased blood flow to the heated area. Increased heart rate will return to baseline levels once heat treatment is removed or stopped. The changes in heart rate during and after therapy may pose significant risks for people with cardiovascular conditions such as arrhythmia.
Increased swelling and inflammation. Heat therapy is not recommended immediately after physical activity, after injury, or during an infection. The heat will worsen pain and prolong healing if used when the tissues are damaged or infected.
Heat therapy has proven pain relief benefits
In summary, there is a growing body of scientific evidence that shows that low-level, superficial heat therapy is an effective, safe and easy to use pain relief option.
Treating pain with heat therapy is relatively cheap and is easy to self administer at home.
Heat therapy offers a non-pharmacological or drug free alternative to pain relief and studies show that using heat therapy can reduce, or in some cases negate the need for pain relief medication.
CancerPal stocks a range of products that can be used to apply heat therapy at home, as well as a range of other non-pharmacological pain relief products in the Pain Relief section of the CancerPal MarketPlace.