Eugenol mainly exerts its analgesic effect by influencing nerve conduction.

Impact on the nerve cell membrane

Eugenol can act on ion channels on the nerve cell membrane. It can inhibit the activity of sodium ion channels. When nerve cells transmit pain signals, the opening of sodium ion channels plays a key role. When sodium ion channels are inhibited, the excitability of nerve cells will be reduced. It is like setting up a “checkpoint” in the “circuit” that transmits pain, reducing the transmission of pain signals.

For example, in the case of toothache, the nerve endings in the dental pulp are activated by stimuli such as inflammation and produce pain signals. Eugenol can act on the cell membranes of these nerve endings and hinder the normal opening of sodium ion channels, thereby preventing the generation and conduction of pain signals and relieving toothache.

Effect on neurotransmitters

Eugenol also affects the release of neurotransmitters. It can reduce the release of some excitatory neurotransmitters (such as glutamic acid, etc.). Glutamic acid is an important excitatory neurotransmitter and plays a key role in the pain conduction pathway of the central nervous system. When eugenol reduces its release, the excitatory signal transmission in the pain conduction pathway will be inhibited.

From the perspective of nerve conduction, neurotransmitters are like “messengers” that transmit pain information from one nerve cell to the next. Eugenol reduces the number of these “messengers”, making it impossible for pain signals to be effectively transmitted between nerve cells, thereby reducing the feeling of pain.

Anti-inflammatory effect assists in analgesia

Eugenol has certain anti-inflammatory properties. Inflammatory reactions are often one of the important causes of pain. For example, in diseases such as arthritis, inflammation at the joint site will stimulate the surrounding nerve endings to produce pain. Eugenol can inhibit the production of some inflammatory mediators (such as prostaglandins, etc.) in inflammatory reactions.

Prostaglandin is a substance that can make nerve endings more sensitive to pain. Eugenol reduces the synthesis of prostaglandins and reduces the sensitivity of nerve endings to pain, thereby indirectly playing an analgesic role. This dual effect of anti-inflammation and analgesia is more obvious in relieving local pain (such as muscle pain, joint pain, etc.).

In addition to its effects on nerve cell membranes and neurotransmitters, what other analgesic mechanisms does eugenol have?

Eugenol may activate the endogenous analgesic system. The human body has an inherent analgesic mechanism, such as the endorphin system. Endorphin is an endogenous opioid-like substance that can bind to opioid receptors and produce analgesia and a sense of pleasure. Eugenol may regulate the release of endorphins or enhance the binding ability of endorphins to opioid receptors in some way.