In the first place, both "cold compresses" and "warm compresses" have the same analgesic ingredients, which are ingredients in a class called nonsteroidal anti-inflammatory drugs (NSAIDs), such as loxoprofen sodium, methyl salicylate, ketoprofen, and felbinac. In other words, whether the compress is cold or warm, the analgesic effect is the same.
Although the ingredients are the same, physiologically speaking, depending on the state of pain, the symptoms can be alleviated by using different cold and warm sensations.
Skin irritating ingredients
There is a difference in the way the temperature is felt at the application site between cold compresses and hot compresses, depending on the skin irritating ingredients listed below. Its ingredients act on the skin, causing sensory stimulation and dilating skin blood vessels.2）
Active ingredients of cooling compresses | Methyl salicylate, ℓ-menthol, peppermint oil |
Active ingredients of warming compresses | Capsicum extract, nonylic acid vanillylamide (synthetic capsicum), nicotinic acid ester |
Since ℓ-menthol acts directly from the skin to the nerves, it does not actually lower the temperature. When ℓ-menthol acts on cold receptors, they respond in the same way as when the temperature is lowered, so you feel cold. Also, no effect is observed when administered orally, but the analgesic effect is exerted only through the stimulatory effect when applied to the skin.。
Capsaicin contained in chili pepper extract has a thermal stimulating effect on the skin. Normally, there are thermoreceptors in the skin that are only stimulated by heat above 43°C, which is enough to cause a tingling sensation, but when capsaicin acts on these receptors, this threshold of ``43°C or above'' is lowered. Produces increased skin blood flow seen during normal skin warming. There are also reports that capsaicin exerts analgesic effects by desensitizing (stimulating sensory nerves and making them unresponsive to other painful stimuli).
State of pain
When you feel pain immediately after an injury, the hormone bradykinin is activated and inflammation occurs. As a result, the area becomes red, swollen, has heat, and pain appears, which is called "acute pain.". For this type of pain caused by a muscle strain, a cold compress may be used to remove heat.
In addition, in case of long-lasting "chronic pain", sympathetic nerves become excited → blood vessels become narrower, blood flow decreases and pain substances are produced → other motor nerves become excited → muscles become tense and the same pain occurs. A ``vicious cycle of pain'' occurs in which substances are formed. If the affected area is stiff and chronically painful due to low back pain or stiff shoulders, a warm compress may be used to improve blood circulation.
To summarize the above contents, you can use them as follows.
Acute pain: The inflamed area becomes hot and swells. → Cool to reduce inflammation. →Use a “cold
Examples of products
compress”Chronic pain: Blood flow is blocked, muscles become stiff, and pain increases. → Warm up and improve blood circulation. →Use a “warm compress”
Examples of products
The compress has a distinctive scent and some people find it refreshing, while others don't like it. Research on the cooling sensation of menthol shows that although there is no difference between men and women regarding the sensitivity of their own use, women tend to rate the cooling sensation higher than men. In addition, an awareness survey conducted on patients prescribed compresses revealed that they preferred compresses that could be used once a day, were thin in shape, and had no odor.6）We know that there is a trend and people are looking for a ``discreet compress''.
However, simply listening to the patient's wishes may cause side effects. Capsaicin is fat-solubleTherefore, it has the property of easily penetrating the skin, and when using it, symptoms of contact dermatitis due to irritation such as redness, itching, and burning sensation may be observed. To avoid causing dermatitis, ① Wipe off moisture thoroughly when applying the patch. ② Change the place you apply it each time to give your skin a rest. ③ Refrain from applying it for a long time. ④ Consider alternative gel or cream type drugs. Let's try something like this.