# Fengyou essence

Fengyou Essence (simplified Chinese: 风油精; traditional Chinese: 風油精; pinyin: Fēngyóu jīng), also named Medicated Oil, is a type of Chinese patent medicine, usually in the form of a liniment or oily liquid with a light green color. It is derived from countries in Southeast Asia where the weather is warm and wet with the prevalence of mosquitoes because it serves a great deal in relieving itchiness. In China, it is sometimes called "panacea oil" as it is believed to alleviate the symptoms of many diseases ranging from coughing and rhinitis to the cold and flu.

## Ingredients

According to China's Food and Medicine Administration, Fengyou Essence ingredients include liquid paraffin, chlorophyll, menthol, methyl salicylate (wintergreen oil), camphor, eucalyptus oil, and eugenol.

## Uses

Fengyou Essence is mainly used after mosquito bites to preventing further itching, for easing headaches or dizziness due to a cold, and for carsickness, pain relief, cooling, and reducing rheumatic pains. It can either be used externally on the skin or taken orally, but people with deep second degree burns or more severe burns are prohibited from using it.
Although taking the product orally is permitted in its instructions, it is advised not to as to avoid adverse reactions such as intestinal stimulations as one of its ingredients methyl salicylate can lead to poisoning if taken too much.

## Mechanism to prevent itchiness

Humans feel like itching their skin after mosquito bites because mosquitoes inject their saliva containing irritable chemicals when drawing out blood. The foreign substances inside the saliva then triggers the body's immune system that releases histamine to help white blood cells get to the bitten area. Menthol and eucalyptus oil in the Fengyou Essence activate specialized nerve cells responsible for sensing temperature, producing the feeling of coldness on the skin. Methyl salicylate could also irritate the skin, causing a burning sensation. Due to the two types of stimulations acting together at the same time, it covers the itchiness.

## Potential side-effects

There are only a few side-effects found by some individuals with allergic constitution. However, if one takes more dosage than recommended, the ingredients of the essence may harm the body. Methyl salicylate and camphor in the essence are both toxic. Under normal usage, after camphor enters the human body, the glucose phosphoric acid dehydrogenase in the body can be combined with the substance very quickly, de-toxifying the material. Then it is discharged out of body through urine. Therefore this will not produce adverse reaction.Yet, studies have shown that taking too much camphor at once can cause poisoning, such as nausea, vomiting, abdominal pain, oropharyngeal irritation and, in severe cases, refractory seizures.

## Contraindications

| 1.Infants and young children | Since skin of small-aged children or infants are more delicate than adults, it is possible for camphor to go through the skin and membrane to damage the red blood cells, hence causing serious problems. |
| 2.Pregnant women | One of the ingredients camphor may traverse the skin to hamper the normal development of infants. |
| 3.Allergic groups | A small number of people are allergic to certain ingredients inside the essence. |
| 4.Favism patients | This group of people lacks 6- phosphoric acid glucose dehydrogenase in their body. After contacting the constituent such as camphor or salicylic acid in the essence, it will increase the likelihood of hemolysis, and aggravate the illness. |
| 5.People with skin damage | Stimulating substances in the essence like menthol and eucalyptus oil can cause serious pain for patients and can slow the healing of wounds. |

## Notable brands

Singaporean Eagle Branded Fengyou Essence (Medicated Oil) is the origin of most of the Fengyou Essence popular in China. Additionally, local brands like "Shuixian", "Baiyunshan", "Longhu" are frequently seen in pharmacy and grocery stores in mainland China.