00:00 / 00:00
Prerequisite basic sciences
Anticonvulsants and anxiolytics: Barbiturates
0 / 7 complete
intoxication and withdrawal p. 594
intravenous anesthetics p. 571
mechanism and use p. 566
naming convention for p. 255
sleep alterations p. 513
barbiturates and p. 566
barbiturate withdrawal p. 594
barbiturate effects p. 566
barbiturates for p. 566
barbiturates p. 566, 594
barbiturates for p. 566
Barbiturates are a class of medications that are used as anticonvulsants to manage seizure disorders; to induce anesthesia in surgical procedures; as anxiolytics to relieve anxiety; and to manage insomnia.
Barbiturates enhance the effect of gamma-aminobutyric acid, or GABA, which is the major inhibitory neurotransmitter in the brain, by binding to its receptor.
It’s pretty well-established that your brain’s really important.
It controls your feelings, your movements, your sleep, your memory… It controls everything, whether you’re aware of it or not.
The cells that make up our brain are called neurons.
Neurons communicate with each other through neurotransmitters.
When one neuron is stimulated, it’ll release excitatory neurotransmitters like glutamate, which bind to receptors on the next neuron.
This causes the next neuron to depolarize and release its own excitatory neurotransmitters, propagating the signal throughout the brain.
Now, we also have inhibitory neurons that will shut down this chain of events.
These neurons release the main inhibitory neurotransmitter in the nervous system, gamma-aminobutyric acid, or GABA, which binds to GABA receptors on other neurons.
These receptors are large multi-unit complexes that form ligand-gated ion channels, which open up to let Cl- ions into the cell.
The influx of negatively charged ions causes hyperpolarization, where the cell’s membrane potential becomes more negative, which means it’s much more difficult for it to depolarize and fire off an action potential, and that means it’s less responsive to stimuli.
Now, there are cases where neurons in the brain start sending out more excitatory signals than normal.
This can occur due to either too much excitation by the excitatory neurotransmitters, or too little inhibition by the inhibitory neurotransmitters like GABA.
Okay, so one way we can decrease the excitatory signals is by enhancing the effect of inhibitory neurons through medication like barbiturates.
Copyright © 2023 Elsevier, its licensors, and contributors. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
Cookies are used by this site.
USMLE® is a joint program of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). COMLEX-USA® is a registered trademark of The National Board of Osteopathic Medical Examiners, Inc. NCLEX-RN® is a registered trademark of the National Council of State Boards of Nursing, Inc. Test names and other trademarks are the property of the respective trademark holders. None of the trademark holders are endorsed by nor affiliated with Osmosis or this website.