Benzodiazepines:- How they Work
The following tries to explain how benzodiazepines work in layman's language. All the information given is gleaned from a publication by Professor C. Heather Ashton, DM, FRCP namely "Benzodiazepines, how they work and how to withdraw" which is based on medical research information from a benzodiazepine withdrawal clinic.
The body produces different brain chemicals which either have a "quietening" or "excitatory" effect on the brain. These natural brain chemicals are in fact neurotransmitters which send messages from one brain cell to another.
An animated example of how benzodiazepines work can be found here.
About 40% of the billions of brain cells, all over the brain, respond to GABA. GABA is the brains "quietening" or tranquillising neurotransmitter. Benzodiazepine and related drugs enhance the effect of GABA.
When one suffers from anxiety, panic attacks etc then the brain becomes "over-active" and it needs the transmitters associated with the "quietening" chemicals to come into action . These respond by sending messages to the brain cells to slow down or to stop and because, as earlier stated, the number of brain cells responsive to these transmitters is high then it has a quietening affect on the brain.
Benzodiazepines consist of similar chemicals to those produced by the body for "quietening" effects and when these are added to those produced naturally, by the body, it means that there are a greater number of transmitters sending out messages to the brain cells resulting in an excessive slow down or shut down of these cells. As a consequence of this increase in the numbers of cells being slowed down the brains output of "excitatory" transmitters is reduced. These excitatory transmitters are vital for normal alertness, memory, co-ordination, emotional responses, heart rate, and blood pressure. The failure to produce enough excitatory transmitters therefore affects the functioning of the aforementioned systems and thereby affects the bodies normal working.
Prolonged use of benzodiazepines forces the brain to make physical
changes to overcome the effects of the drug which is known as
“tolerance” which then results in GABA, the natural calming chemical, produced by the brain becoming less effective.
When one tries to discontinue the drug, after long term use, these
adaptations produced when becoming tolerant to the drug force the brain to go into excessive drive. This results in anxiety, memory problems, panic attacks, paranoia, and agorophobia. A combination of these symptoms is known as the “withdrawal syndrome” and is the reason for people experiencing symptoms when undertaking a reduction or withdrawal programe.
Eventually the brain will return to producing the natural GABA
state at which time the withdrawal will be complete. The time to get
back to natural GABA activity varies from person to person and explains why the withdrawal process is an individual thing.
