Nervous System and Medications Overview

Nervous System Overview

• Branches of Nervous System:
  • Central Nervous System (CNS): Comprises the brain and spinal cord; made up of billions of neurons that facilitate communication between the brain and body.
  • Processes information both internally (body's condition) and externally (environment).
  • Peripheral Nervous System (PNS): Includes all nerves outside the CNS. Further divided into:
  • Somatic Nervous System: Controls voluntary movements (e.g., lifting a hand).
  • Autonomic Nervous System: Controls involuntary actions (e.g., digestion).

Function of the Brain

• The brain reacts to external stimuli (like heat) by activating sweat glands to regulate temperature.
• Internal responses are managed through mechanisms such as shivering when cold, to generate heat.

Medications for the Nervous System

• Categories of Medications:
  • Used for treating various conditions such as:
  • Pain and fever
  • Anxiety
  • Depression
  • Seizures
  • Schizophrenia

Concept of Psychotropic Medications

• Definition: Medications that affect mood, emotion, and behavior.
• These medications act on both the CNS and PNS, impacting the entire body system.
  • Example: An anxiety medication can also alleviate pain due to its properties.
• Most act on the synaptic gap between the nerves to facilitate neurotransmitter function.
• Can cross the blood-brain barrier, leading to potential side effects.

Peripheral Nervous System Detailed

• Divisions:
  • Somatic: Voluntary control over muscles.
  • Autonomic: Involuntary control over internal organs, which contains:
  • Sympathetic Nervous System (SNS): Initiates 'fight or flight' responses.
  • Parasympathetic Nervous System (PNS): Promotes 'rest and digest' state.

Neurotransmitters

• Acetylcholine: Released by cholinergic nerve cells to relax the body (PNS).
• Norepinephrine: Released by adrenergic nerve cells to excite the body (SNS).

Medications in Autonomic Actions

• Sympathomimetics: Mimic SNS responses to aid in fight or flight (e.g., increase heart rate, bronchodilation).
• Contradictions: Use caution with patients with hyper sensitivity, hypertension, heart issues, etc.

Common Medications Discussed

• Norepinephrine (LevaMed): Used for blood pressure maintenance.
• Epinephrine: Used for severe allergic reactions or cardiac arrest.
• Beta Blockers: Used to manage heart rhythm disorders and lower blood pressure (often end in -olol).

Pain and Fever Medications

• Analgesics: Reduce pain without eliminating sensation. Types include:
  • NSAIDs (e.g., Ibuprofen, Aspirin): Manage pain, inflammation, and fever, but must be careful of GI effects.
  • Acetaminophen (Tylenol): Reduces pain/fever but has no anti-inflammatory effect.
  • Safe limits for adults: Generally should be less than 4 grams per day.
  • Narcotic analgesics (e.g., Morphine, Fentanyl): Strong pain relief but carry addiction risks and side effects of respiratory depression and blood pressure changes.

Key Considerations

• Patient Monitoring: Always assess patient's history, allergies, and current medication regimen.
• Drug Interactions: Be aware of combined medications that may lead to overdose or enhanced side effects.

Conclusion

• Ensure robust knowledge of the nervous system and related medications. Always be ready to answer questions and clarify doubts during review sessions.