5.8 Effects of Drugs On Nervous Coordination

Drugs affect nervous coordination by interfering with the normal functioning of the nervous system. They can alter mood, emotions, and behavior by changing brain chemistry. This topic covers narcotic drugs, drug addiction, drug tolerance, and their effects on the central nervous system.

Definition

Narcotic: A narcotic is a group of substances when administered diminish the perception of pain. Narcotics bind to certain painkilling sites in the brain.

Drug Addiction: Drug addiction is a dependence on an illegal drug or a medication.

Drug Tolerance: Drug tolerance is a person's diminished response to a drug, which occurs when the drug is used repeatedly and the body adapts to the continued presence of the drug.

Main Idea

• Narcotics are drugs that act as agents which interact with the normal nervous activity.
• With constant use, they build up in the brain and block the production of endorphins, the brain's natural painkilling chemicals.
• Their side effects are inhibition of the endocrine and autonomous nervous system.
• Common narcotic drugs are heroin, Cannabis, nicotine, and alcohol.
• Drug addiction is a dependence on an illegal drug or a medication.
• Drug tolerance is a person's diminished response to a drug.
• Drugs interact with the brain and body to alter moods, emotions, and behaviors by changing brain chemistry.

Core Concept

• Narcotic = substance that diminishes perception of pain
• Narcotics = bind to painkilling sites in the brain
• Endorphins = brain's natural painkilling chemicals
• Common narcotics = heroin, Cannabis, nicotine, alcohol
• Drug addiction = dependence on a drug
• Drug tolerance = diminished response to a drug
• Effects on CNS = alter moods, emotions, behaviors
• Regions affected = brain stem, limbic system, cerebral cortex
• Depressants = slow down CNS
• Stimulants = increase heart rate, respiratory rate

Detailed Explanation

Narcotic Drugs

• A narcotic is a group of substances when administered diminish the perception of pain.
• Narcotics bind to certain painkilling sites in the brain.
• With constant use, they build up in the brain and block the production of endorphins, the brain's natural painkilling chemicals.
• Their side effects are inhibition of the endocrine and autonomous nervous system etc.
• The narcotics are the drugs that act as agents which interact with the normal nervous activity.

Common Narcotic Drugs

Heroin

• Heroin gives a feeling of euphoria along with relief of pain.
• Side effects can include:
• Nausea
• Vomiting
• Respiratory and circulatory depression leading to death

Cannabis

• It is the dried flowering tops, leaves and stem of Indian hemp plant Cannabis sativa.
• It includes marijuana and hashish.
• Usually the users report a mild euphoria, along with alterations in vision and judgement.
• Intoxication is recognised by the presence of:
• Hallucinations
• Anxiety
• Depression

Nicotine

• It is an alkaloid derived from tobacco.
• When smoking a cigarette, nicotine is quickly distributed to all body organs.
• In peripheral nervous system, nicotine stimulates postsynaptic receptors (like acetylcholine) and leads to increased skeletal muscular activity.
• It also increases heartbeat rate and blood pressure.

Alcohol

• Alcohol acts as a depressant and slows down the nervous communication.
• Its short term effects are impairment of vision, judgment and alertness.
• Long term chronic drinking can damage nervous system, liver and pancreas.

• Individuals who eliminate addictive substances from their lives often feel withdrawal symptoms.
• Alcohol withdrawal refers to a group of symptoms that may occur from suddenly stopping the use of alcohol.
• The symptoms are:
• Feeling of anxiety
• Irritability
• Depression
• Headache
• Hallucinations

Inhalants

• These are volatile organic chemicals, commonly referred to as "glue sniffing".
• Inhalant abuse now includes aerosols e.g., hair spray and anaesthetics e.g., ether etc.
• Inhalants rapidly start euphoria followed by central nervous system depression.
• Deep breathing of the toxic vapours may result in hallucinations or even death.

Drug Addiction and Drug Tolerance

• Drug addiction is a dependence on an illegal drug or a medication.
• You may want to quit, but most people find they can't do it on their own.

Drug Tolerance: - Drug tolerance is a person's diminished response to a drug, which occurs when the drug is used repeatedly and the body adapts to the continued presence of the drug e.g. caffeine and nicotine.

Caffeine

• Caffeine is a drug, and individuals can develop both tolerance and a form of dependence.
• Caffeine tolerance: Tolerance to caffeine means that the body becomes accustomed to its effects, requiring higher doses to achieve the same level of alertness or stimulation.
• Caffeine addiction: It does not cause classic addiction the way some drugs do.
• Harmful effects of caffeine: These include:
• Insomnia
• Rapid heart rate
• Anxiety
• Frequent urination
• Digestive issues
• Fatigue
• High blood pressure
• Irritability
• Tremors

Nicotine

• Nicotine is the chemical in tobacco that makes it hard to quit.
• Nicotine tolerance: It occurs when the body requires increasing amounts of nicotine to achieve the same effects initially felt with lower doses.
• Nicotine addiction: Nicotine produces pleasing effects in your brain, but these effects are temporary. So you reach for another cigarette. The more you smoke the more nicotine you need to feel good.

• Caffeine and nicotine both cause the brain to release dopamine, but the release from caffeine is much smaller.
• Nicotine changes how the brain works, making it one of the most addictive substances in the world.

• Cancer
• Nausea
• Dizziness
• Emphysema
• Infertility
• Insomnia
• Cardiovascular diseases
• Headache
• Mouth ulcer

Effects of Drug Addiction and Tolerance on the Central Nervous System

• Drugs are chemicals that interfere with the way neurons normally send, receive, and process information.
• Some drugs can activate neurons because their chemical structure mimics that of a natural neurotransmitter.
• Drugs interact with the brain and body to alter moods, emotions, and behaviors by changing brain chemistry.
• Regions of the brain affected by drug abuse are the brain stem, limbic system, and cerebral cortex.
• All depressants work by slowing down the functioning of the central nervous system.
• Stimulants can produce a number of effects on the body such as increased heart rate, improved concentration, increased respiratory rate etc.

Summary Table of Narcotic Drugs

Summary Table of Drug Tolerance and Addiction

Intermediate Level

Narcotic Drugs

Drug Addiction and Tolerance

Effects on CNS

Brain Regions Affected

Formula / Mathematical Form

Not applicable to this topic.

Solved Example

Not applicable to this topic (descriptive topic).

Important Points

• 1. Narcotics diminish the perception of pain.
• 2. Narcotics bind to painkilling sites in the brain.
• 3. Constant use blocks endorphins.
• 4. Side effects include inhibition of endocrine and autonomic nervous system.
• 5. Heroin gives euphoria and pain relief.
• 6. Cannabis includes marijuana and hashish.
• 7. Nicotine is an alkaloid derived from tobacco.
• 8. Alcohol acts as a depressant.
• 9. Inhalants are volatile organic chemicals.
• 10. Drug addiction is dependence on a drug.
• 11. Drug tolerance is diminished response to a drug.
• 12. Caffeine tolerance requires higher doses.
• 13. Nicotine tolerance requires increasing amounts.
• 14. Nicotine is highly addictive.
• 15. Drugs alter moods, emotions, and behaviors.
• 16. Brain regions affected: brain stem, limbic system, cerebral cortex.
• 17. Depressants slow down CNS.
• 18. Stimulants increase heart rate, concentration, respiratory rate.
• 19. Withdrawal symptoms occur when stopping drugs.
• 20. Drugs can cause serious harm and death.

Remember

• - Narcotic = substance that diminishes perception of pain
• - Narcotics = bind to painkilling sites in the brain
• - Endorphins = brain's natural painkilling chemicals
• - Common narcotics = heroin, Cannabis, nicotine, alcohol
• - Drug addiction = dependence on a drug
• - Drug tolerance = diminished response to a drug
• - Effects on CNS = alter moods, emotions, behaviors
• - Regions affected = brain stem, limbic system, cerebral cortex
• - Depressants = slow down CNS
• - Stimulants = increase heart rate, respiratory rate

Common Mistakes

• 1. Confusing narcotics and drugs — Narcotics are a type of drug that reduces pain.
• 2. Thinking all drugs are narcotics — Not all drugs are narcotics.
• 3. Forgetting the role of endorphins — Narcotics block endorphin production.
• 4. Mixing up addiction and tolerance — Addiction = dependence; tolerance = diminished response.
• 5. Thinking caffeine is not addictive — Caffeine can cause tolerance and mild dependence.
• 6. Underestimating nicotine addiction — Nicotine is highly addictive.
• 7. Forgetting the effects on the brain — Drugs alter moods, emotions, behaviors.
• 8. Mixing up the brain regions — Brain stem, limbic system, cerebral cortex.
• 9. Confusing depressants and stimulants — Depressants slow CNS; stimulants increase activity.
• 10. Believing drugs are not dangerous — Drugs can cause serious harm and death.

Quick Revision

A narcotic is a group of substances when administered diminish the perception of pain. Narcotics bind to certain painkilling sites in the brain. With constant use, they build up in the brain and block the production of endorphins, the brain's natural painkilling chemicals. Their side effects are inhibition of the endocrine and autonomous nervous system etc. The narcotics are the drugs that act as agents which interact with the normal nervous activity. Common narcotic drugs are heroin, Cannabis, nicotine and alcohol etc. Heroin gives a feeling of euphoria along with relief of pain. Cannabis includes marijuana and hashish. Nicotine is an alkaloid derived from tobacco. Alcohol acts as a depressant and slows down the nervous communication. Inhalants are volatile organic chemicals. Drug addiction is a dependence on an illegal drug or a medication. Drug tolerance is a person's diminished response to a drug, which occurs when the drug is used repeatedly and the body adapts to the continued presence of the drug. Drugs interact with the brain and body to alter moods, emotions, and behaviors by changing brain chemistry. Regions of the brain affected by drug abuse are the brain stem, limbic system, and cerebral cortex. All depressants work by slowing down the functioning of the central nervous system, while stimulants can produce a number of effects on the body such as increased heart rate, improved concentration, increased respiratory rate etc.

60-Second Revision

• Narcotic = substance that diminishes perception of pain
• Narcotics = bind to painkilling sites in the brain
• Endorphins = brain's natural painkilling chemicals
• Common narcotics = heroin, Cannabis, nicotine, alcohol
• Drug addiction = dependence on a drug
• Drug tolerance = diminished response to a drug
• Effects on CNS = alter moods, emotions, behaviors
• Regions affected = brain stem, limbic system, cerebral cortex
• Depressants = slow down CNS
• Stimulants = increase heart rate, respiratory rate
• Warning: Narcotics block endorphins; depressants slow CNS; stimulants increase activity

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