National Certified Addiction Counselor, Level 2 (NCAC II) Practice Exam Exam

Which neurotransmitter acts as an inhibitor and mediates the actions of many drugs of abuse?

1. Dopamine

2. Serotonin

3. Norepinephrine

4. GABA

The correct answer is: GABA

GABA, or gamma-aminobutyric acid, is a key inhibitory neurotransmitter in the central nervous system. Its primary function is to reduce neuronal excitability throughout the nervous system. This inhibitory action is essential for maintaining a balance in brain activity, and it's significantly involved in the effects of many substances of abuse. Many drugs that are commonly abused, such as alcohol, benzodiazepines, and barbiturates, enhance GABA's effects, leading to increased inhibition within the brain. This results in sedative, anxiolytic (anxiety-reducing), and muscle relaxant effects that can be appealing to individuals seeking relief from discomfort or stress. In the context of substance use, the interaction with GABA can also contribute to the development of tolerance and dependence, as individuals may require larger doses over time to achieve the same inhibitory effects. Understanding the role of GABA in these processes is crucial for addiction counseling, as it highlights the biological underpinnings of substance use disorders and addiction.