Orphenadrine is a so-called anticholinergic with an effect on the central nervous system. On the peripheral nervous system, orphenadrine has very little effect. In addition, it shows properties of an antihistamine as well as those of a local anaesthetic.
The mechanism of action is primarily based on a blockade of glutamate receptors. Glutamate is a very important excitatory neurotransmitter in the human brain. When blocked by orphenadrine, muscles become less excited and relaxation occurs.
Orphenadrine is absorbed into the blood mainly through the gastrointestinal tract. Plasma protein binding is 95% and plasma half-life is between 13-20 hours. Degradation of the drug occurs entirely in the cells of the liver.
The agents amantadine, quinidine, MAO inhibitors, and some tricyclic antidepressants may potentiate the anticholinergic effect of Orphenadrine. Orphenadrine may potentiate the effects of L-dopa. There is a risk of hypothermia if chlorpromazine is taken concomitantly. The consumption of alcohol should be avoided while taking Orphenadrine.