Benzodiazepines (BZs) are a range of anti-anxiety drugs, which include trade names like Valium and Diazepam. BZs work by enhancing the action of the neurotransmitter GABA (gamma-aminobutyric acid). GABA tells neurons in the brain to 'slow down' and 'stop firing' and around 40% of the neurons in the brain respond to GABA. This means that BZs have a general quietening influence on the brain and consequently reduce anxiety, which is experienced as a result of the obsessive thoughts.