Laudanosine or N-methyltetrahydropapaverine is a recognized metabolite of atracurium

Atracurium

Atracurium besylate is a neuromuscular-blocking drug or skeletal muscle relaxant in the category of non-depolarizing neuromuscular-blocking drugs, used adjunctively in anesthesia to facilitate endotracheal intubation and to provide skeletal muscle relaxation during surgery or mechanical...

 and cisatracurium

Cisatracurium

Cisatracurium is a neuromuscular-blocking drug or skeletal muscle relaxant in the category of non-depolarizing neuromuscular-blocking drugs, used adjunctively in anesthesia to facilitate endotracheal intubation and to provide skeletal muscle relaxation during surgery or mechanical ventilation...

. Laudanosine decreases the seizure threshold, and thus it can induce seizures if present at sufficient threshold concentrations; however such concentrations are unlikely to be produced consequent to chemodegradable metabolism of clinically administered doses of cisatracurium

Cisatracurium

Cisatracurium is a neuromuscular-blocking drug or skeletal muscle relaxant in the category of non-depolarizing neuromuscular-blocking drugs, used adjunctively in anesthesia to facilitate endotracheal intubation and to provide skeletal muscle relaxation during surgery or mechanical ventilation...

 or atracurium

Atracurium

Atracurium besylate is a neuromuscular-blocking drug or skeletal muscle relaxant in the category of non-depolarizing neuromuscular-blocking drugs, used adjunctively in anesthesia to facilitate endotracheal intubation and to provide skeletal muscle relaxation during surgery or mechanical...

.

Laudanosine also occurs naturally in minute amounts (0.1%) in opium

Opium

Opium is the dried latex obtained from the opium poppy . Opium contains up to 12% morphine, an alkaloid, which is frequently processed chemically to produce heroin for the illegal drug trade. The latex also includes codeine and non-narcotic alkaloids such as papaverine, thebaine and noscapine...

, from which it was first isolated in 1871. Partial dehydrogenation

Dehydration reaction

In chemistry and the biological sciences, a dehydration reaction is usually defined as a chemical reaction that involves the loss of water from the reacting molecule. Dehydration reactions are a subset of elimination reactions...

 of laudanosine will lead to papaverine

Papaverine

Papaverine is an opium alkaloid antispasmodic drug, used primarily in the treatment of visceral spasm, vasospasm , and occasionally in the treatment of erectile dysfunction...

, the alkaloid found in the opium poppy plant (Papaver somniferum).

Laudanosine is a benzyltetrahydroisoquinoline alkaloid

Alkaloid

Alkaloids are a group of naturally occurring chemical compounds that contain mostly basic nitrogen atoms. This group also includes some related compounds with neutral and even weakly acidic properties. Also some synthetic compounds of similar structure are attributed to alkaloids...

. It has been shown to interact with GABA receptor

GABA receptor

The GABA receptors are a class of receptors that respond to the neurotransmitter gamma-aminobutyric acid , the chief inhibitory neurotransmitter in the vertebrate central nervous system...

s, opioid receptor

Opioid receptor

Opioid receptors are a group of G protein-coupled receptors with opioids as ligands. The endogenous opioids are dynorphins, enkephalins, endorphins, endomorphins and nociceptin. The opioid receptors are ~40% identical to somatostatin receptors...

s, and nicotinic acetylcholine receptor

Nicotinic acetylcholine receptor

Nicotinic acetylcholine receptors, or nAChRs, are cholinergic receptors that form ligand-gated ion channels in the plasma membranes of certain neurons and on the postsynaptic side of the neuromuscular junction...

s, but not benzodiazepinergic or muscarinic receptors which are also involved in epilepsy and other types of seizures.