ChEBI

Any minor or unwanted substance introduced into the environment that can have undesired effects.

A molecular entity capable of accepting a hydron from a donor (Bronsted acid).

Any substance that inhibits the action of N-methyl-D-aspartate (NMDA) receptors. They tend to induce a state known as dissociative anesthesia, marked by catalepsy, amnesia, and analgesia, while side effects can include hallucinations, nightmares, and confusion. Due to their psychotomimetic effects, many NMDA receptor antagonists are used as recreational drugs.

An agent capable of relieving pain without the loss of consciousness or without producing anaesthesia. In addition, analgesic is a role played by a compound which is exhibited by a capability to cause a reduction of pain symptoms.

A xenobiotic (Greek, xenos "foreign"; bios "life") is a compound that is foreign to a living organism. Principal xenobiotics include: drugs, carcinogens and various compounds that have been introduced into the environment by artificial means.

A poison that interferes with the functions of the nervous system.

An agent capable of relieving pain without the loss of consciousness or without producing anaesthesia. In addition, analgesic is a role played by a compound which is exhibited by a capability to cause a reduction of pain symptoms.