CNS agents, or central nervous system agents, are substances that affect the brain and spinal cord. They can alter mood, perception, and behavior, and are often used to treat various medical conditions such as anxiety, depression, and epilepsy. These agents can be classified into several categories, including antidepressants, antipsychotics, and anticonvulsants. These medications work by influencing neurotransmitters, which are chemicals that transmit signals in the brain. For example, selective serotonin reuptake inhibitors (SSRIs) increase levels of serotonin, a neurotransmitter linked to mood regulation. While CNS agents can be effective in managing symptoms, they may also have side effects and require careful monitoring by healthcare professionals.