Effect Of Drugs In The Body

Question 0

Routes of administration 1. Oral

Answer 0

Oral: through the mouth digested through gastrointestinal tract and into the stomach, then through the small intestine and into the bloodstream. Only75% of the drug is absorbed through this process. Factors that affect the absorption of the drug: the acidic level of our stomach, undigested food and how often we take the drug.

Question 1

What is pharmacokinetics?

Answer 1

Pharmacokinetics is the study of the movement of drugs through the body.
The 4 process are absorption, distribution, metabolism, and elimination

Question 2

Routes of administration 2. Absorption

Answer 2

Through the mucus membranes: snorting of the drug, it binds to the mucus membranes in the nasal cavities.
Absorption through mucus membranes in the mouth can be used for prescription drugs, chewing tobacco and nicotine chewing gums.
Absorption through the skin-drug slowly diffuses through the skin and into the bloodstream.

Question 3

Routes of administration 3. Inhalation

Answer 3

Absorption of the lungs into the heart and bloodstream. It is the fastest and simplest way for a drug to reach the bloodstream. It is commonly used in anesthesia because it can be accurately measured.

Question 4

Routes of administration 4. Injection

3 types

Answer 4

Injected through a needle and syringe. By passes the digestion process and reaches the bloodstream faster.
Intravenous- injected straight into the vein. Good for accurate measure, but it is irreversible ( ex. Overdose)
Intramuscular- injected into the muscle, absorbed through muscle capillaries. Process takes longer than I.V. ( ex. Immunizations)
Subcutaneous- injected under the skin. Slowest of all three, but a steady absorption (ex. Insulin)

Question 5

Which routes of drug administration are the faster and wich are slower?

Answer 5

Inhalation: fastest
Oral: is the slowest

Question 6

Review the circulatory system and how blood circulates around the body.

Answer 6

The veins bring in deoxygenated blood into the heart through the right atrium the passes through the right ventricle. Then, it is pumped to the lungs where it becomes oxygenated.
After, it returns to the heart through the left atrium and the through the left ventricle and out of the aorta.
Veins bring blood to the heart through the right side of the heart. Arteries bring blood away from the heart through the left side of the heart.

Question 7

Which organs in the body are involved in drug metabolism and drug excretion?

Answer 7

The liver is involved in metabolization known as Hepatic Biodegradation. Also biotransformation is involved in the liver.
The kidneys are involved in drug elimination; this is the main way of elimination.
The lungs, skin, and breast milk
The small intestines play a little role in elimination.

Question 8

Review the half-life table. For example, how many half-lives would it take for a drug to reach 25% concentration in the body?

Answer 8

The first half life brings it to 50 % of the concentration in your body, the second half life would bring it down to 25% of the concentration, therefore, it will take the drug 2 half lives to reach 25%.

Question 9

Standard drug test screen for which 5 drugs?How do urine and hair analysis for drugs differ?

Answer 9

The 5 drug detected in standard drug test are cannabinoids,opiates, cocaine, amphetamine and PCP
Short: urine analysis are good for detecting recent chronic use, while the hair follicle detects most drugs for up to 90 days after use.
Urine analysis detect recent and chronic use. Drugs are detected for up to a couple of hours or days (1-7) after use. Some drugs may be detectable for several weeks for chronic users.
Hair follicle analysis: typically 20-90 strands of hair and test 1.5 inches closest to the scalp. Used only for chronic users. It generally takes 2 weeks for drug metabolites to be detected. Metabolites can be detected for up to 90 days after use.

Question 10

What are some factors discussed in class that affect drug metabolism?

Answer 10

Genetic: enzyme P450 (breaking down the drugs) chemicals released  to he liver to break down drugs. One example would be that Asians lack one enzyme, which breaks alcohol, therefore, they get intoxicated faster.
Environmental: juice and drugs are sometimes dangerous combination. Combination of drugs with food, beverages other drugs could have adverse effects
Physiology: depending on weight and gender how drugs affect the body. Female have less enzymes to break down alcohol. In class example, alcohol, as more alcohol someone drinks as more tolerant someone cN become and needs more alcohol to get drunk

Question 11

Which arts of the nervous system are in the central nervous system? Which parts are in the peripheral nervous system?

Answer 11

Central Nervous System- brain and spinal cord
Peripheral Nervous System- from the spinal cord to the rest of the body (nerves that connect to muscles and glands) and vice versa.
Somatic- voluntary
Automatic- involuntary

Question 12

Review the basic functions of the sympathetic and parasympathetic nervous system.

Answer 12

Sympathetic: fight or flight response
Parasympathetic: rest and digest (control things in the body that happen automatically such as heartbeat, breathing, blood flow, digestion)

Question 13

What Are the basic functions discussed in class for each of the 4 lobes of the brain?

Answer 13

Frontal lobe- motor processing and higher order of thinking (planning/ reasoning)
Temporal lobe: audition
Parietal lobe: orientation
Occipital lobe: vision

Question 14

Drugs that affect the 4 lobes of the brain

Answer 14

Frontal lobe : alcohol
Temporal lobe: alcohol and dissociative drugs
Parietal lobe: alcohol
Occipital lobe: LSD, mescaline, mushrooms

Question 15

Review the basic functions of the brain regions discussed in class and listed on your lecture notes. Part 1.

Answer 15

Amygdala- part of the limbic system, which is responsible for emotion regulation. Over stimulation of this area can be interpreted by the brain as fear.
Hippocampus- located in the temporal lobe, tis area of the brain helps form memories, it is very disrupted by alcohol (blacking out)
Basal ganglia- motor function. It is activated by many different drugs including ecstasy, meth, cocaine.

Question 16

Review the basic functions of the brain regions discussed in class and listed on your lecture notes. Part 2

Answer 16

Thalamus relay center. Distinguishes between sensory and motor information, helps to get information to the correct place.
Hypothalamus- feed, fight,flee, fuck
Reticular formation- excites the brain and activities the cortex. Class example: slapping a book on a desk would activate the reticular formation
Substansia Nigra- produces dopamine
Periaqueductal Gray- (plays huge role in pain management) it releases endorphins to aid in pain management. Opiates significantly affect this region.
Cerebellum- balanced and coordination, connects with the basal ganglia, affected by alcohol
Pons- respiration sleep, Medulla - regulates heart function, connect to the sympathetic ns

Question 17

Review the neurotransmitters discussed in class and where ther are synthesized (made) in the brain.

Answer 17

Glutamate: excitatory and found throughout the brain, made in the brain amino acid.
Dopamine: is created in several areas of he brain
GABA: is synthesized in two compartments of the brain
Acetylcholine: only made in three certain parts, this also helps with muscle contractions and motor functions
Norepinephrine
Seratonin

Question 18

Review the specify drugs discussed in class, which neurotransmitters they affect, and whether each in an agonist or antaginist.

Answer 18

ACh is affected by:
Curare, botulin toxin, black widow venom, tetanus, tear gas
Glutamate is affected by:
MSG, phencyclidine, carbon monoxide

Question 19

How are the neurotransmitters metabolized or broken down after they bind to receptors?

Answer 19

After the neurotransmitters bind to the receptor, the mess must be cleaned up:

1. Degraded by enzymes: ex. Ach is broken down AChE.
2. It can be taken back up to presynaptic terminal called Re-uptake. The neurotransmitter is either recycled or destroyed by enzymes.
   - neurotransmitters are metabolized by reuptake, which recycles neurotransmitters back to the cell to be released again in the future (or be destroyed)
   - neurotransmitters are broken down by deactivating the enzymes

Question 20

Review the ways that drugs can act as agonist or antagonist ( block reuptake vs. stimulate)

Answer 20

Agonist increase the action of a neurotransmitter. Blocks reuptake and degrading enzymes, stimulates receptors/release, promotes synthesis.
Antagonist decreases the action of a neurotransmitter. Stimulate reuptake, and blocks the receptors, inhibits the sythesis and block the release. An antagonist drug stimulates deactivating enzymes.

Question 21

What is the difference between recreational and instrumental drug use?

Answer 21

Recreational- taking drugs for sole purpose of psychoactive properties (get high)
Instrumental- taking drugs for a socially approved goal
Remember: both licit and illicit drugs can be taken recreationally and instrumentally.

Question 22

What are some difference between drug misuse and drug abuse?

Answer 22

Misuse: form of drug-taking behavior in which a prescription or no prescription (over the counter) drug used inappropriately
Abuse: form of drug taking that results in some form of physical, mental or social impairment.

Question 23

What is the difference between physical and psychological dependence?

Answer 23

Physical dependence: occurs when the use of a drug is to avoid withdrawal symptoms if the drug is not take

• withdrawal (effect felt from a day to maybe a week)
• abstinence syndrome

Psychological dependence: occurs when the motivation to use a drug is based on craving for the pleasurable effects

• positive reinforcement
• negative reinforcement

Question 24

What is the difference between acute and chronic toxicity?

Answer 24

Acute toxicity: the physical psychological harm a drug might cause to a user immediately or soon after the drug is ingested
- delirium, lethal overdose
Chronic toxicity: the physical or psychological harm a drug might cause over a long period of time
- tolerance, dependence

Question 25

What makes a drug a schedule I vs. schedule II?

Answer 25

Schedule I: high potential for abuse, no accepted medical use; ex. Heroine, marijuana
Schedule II: high potential for abuse, some accepted medical use; ex. Codeine, morphine

Question 26

What is a drug tolerance? Review the differences between metabolic tolerance, pharmacodynamic tolerance, behavioral conditioning.

Answer 26

Drug Tolerance: a gradually diminished physical or psychological effect of a drug upon repeated administration (over time, need a larger amount to achieve effect originally obtained by smaller amount)
Three mechanisms
Metabolic tolerance (the liver breaks down the drug faster after repeated administrations than it did initially)
Pharmacodynamic tolerance (receptors that have been stimulated by the drug over time decrease in number or become less sensitive to it)
Down regulation
Behavioral conditioning (conditioning to a context)
Cross-tolerance

Question 27

What are the dose curves? What do they tell you about drug safety? What does a lethal dose of 40 tell you about a drug? What does an effective of 40 tell you about a drug?

Answer 27

Dose response curves: minimal dose necessary to produce the intended drug effect on a give percentage of the population under study (ex. ED 50: 50% of the population under the study produces the intended drug effect, ED 100: 100% of the population under study produces the intended drug effect)
Lethal dose: minimal dose necessary to produce death in a given percentage of the population under the study ( ex. LD 50: 50% of people die)

Question 28

Review the different types of drug interactions discussed in class.

Answer 28

Additive interaction: mixing thing
Hyperadditive
Potentiation
Antagonism
Food drug interactions
Grapefruit juice interaction