Overview of Drug Interaction with the Brain

Introduction

• Most people take medicine in their lifetime.
• Lack of knowledge about how drugs work.
• Drugs impact physical feelings, thoughts, and behavior by altering brain cell communication.

Drug Administration and Bloodstream Entry

• Drugs must reach the bloodstream before affecting the brain.
• Methods of Administration:
  • Oral: Slowest; absorbed via the digestive system.
  • Inhalation: Faster entry into the bloodstream.
  • Intravenous Injection: Direct and quick bloodstream entry.
• Blood-Brain Barrier:
  • A protective layer that guards the entrance to the brain.
  • Drugs need specific chemical compositions to pass through.

Interaction with Brain's Neurons and Synapses

• Neurons: Brain cells with a nucleus, dendrites, and an axon.
• Synapses: Allow electrochemical signal exchange between neurons.
• Neurotransmitters: Chemical signals regulating behaviors, emotions, and cognition.

Neurotransmitter Functions

• Inhibition: Limits the receiving neuron's activity.
• Excitation: Creates new signals spreading through the network.
• Reabsorption and Degradation: Leftover neurotransmitters are processed.

Drug Effectiveness

• Manipulates synaptic transmissions at different phases.
• Antidepressants (SSRIs): Inhibit serotonin reabsorption, enhancing mood regulation.
• Painkillers (e.g., Morphine): Increase serotonin and noradrenaline, affecting energy and pleasure.
• Tranquilizers: Boost GABA production, resulting in relaxation.

Effects of Illegal and Elicit Drugs

• Crystal Meth: Long-lasting dopamine release, activates noradrenaline receptors.
• Cocaine: Blocks dopamine and serotonin reuptake, increases euphoria and energy.
• Hallucinogens (LSD, Mescaline, DMT): Block serotonin release, affect perception and behavior.

Risks and Control of Drug Usage

• Drugs can permanently alter brain chemistry with repeated use.
• Some drugs are controlled/illegal due to potential dangers.

Conclusion

• Limited knowledge of drugs' positive and negative effects.
• Research and Development:
  • Enhances medicine effectiveness.
  • Potential for treating complex medical issues as understanding grows.