Final answer:
A barbiturate overdose can cause symptoms such as agitation, irritability, seizures, and a hyperexcitable state. These symptoms result from the effects of barbiturates on the GABAergic system in the brain.
Step-by-step explanation:
The OD that causes agitation, irritability, seizures, and a hyperexcitable state is a barbiturate overdose. Barbiturates are a type of sedative-hypnotic drug that can have these effects when taken in excessive amounts. In an overdose, barbiturates can disrupt the normal activity of the central nervous system, leading to symptoms such as agitation, irritability, and seizures.
These symptoms can be attributed to the effects of barbiturates on the GABAergic system, which is involved in regulating brain activity. Barbiturates enhance the inhibitory effects of GABA, resulting in a decrease in the excitability of neurons. However, in an overdose, the excessive stimulation of GABA receptors can lead to hyperexcitability and the symptoms mentioned.
If someone is experiencing an overdose on barbiturates, it is important to seek immediate medical attention.