This medication works in a very similar fashion as other benzodiazepine drugs. It attaches itself to a GABA receptor subunit and this helps decrease certain nerve activities. Thus, racing thoughts, fear, dread, or other rapid movement signaled by the brain is slowed down.
Diazepam seems to have the most effect on the following nervous system components: the limbic system, thalamus, and hypothalamus. This is part of what slows the brain down and allows it to function more normally.
The cerebral cortex is affect. This is the core of the inhibitory process which helps stop activity that causes mental illness symptoms as described above.
It can also prevent anxiety associated with insomnia and it can also help control seizures. (However, this medication is not usually the first choice of a drug for epilepsy patients.)