Drugs of Abuse

Question 1

what do all addictive drugs activate

Answer 1

the mesolimbic dopamine system

Question 2

what are the drugs of abuse that are CNS depressants

Answer 2

Ethanol
Benzodiazepines
Barbiturates

Question 3

mechanism of action of ethanol

Answer 3

influences several cellular functions –> GABA-A receptors, Kir3/GIRK channels, adenosine reuptake, glycine receptors, NMDA receptors, 5-HT3 receptors

Question 4

preferred drug of choice for treating alcohol withdrawal syndrome

Answer 4

Benzodiazepines

Question 5

Benzos used for withdrawal syndrome in elderly and those with liver disease and why

Answer 5

Lorazepam and Oxazepam because they do not undergo phase I metabolism with CYP3A4 so no liver involvement

Question 6

FDA approved treatment for alcoholism

Answer 6

Naltrexone
Acamprosate
Disulfiram

Question 7

how does disulfiram work in treatment of alcoholism

Answer 7

• inhibitor of aldehyde dehydrogenase causing an aversion to drinking
• if ethanol consumed while taking disulfiram, acetaldehyde accumulation –> nausea, headache, flushing, hypotension

Question 8

how does naltrexone work in treatment of alcoholism

Answer 8

-opioid receptor antagonist that reduces craving for alcohol

Question 9

how does acamprosate work in treatment of alcoholism

Answer 9

NMDA receptor antagonist

long term use of alcohol –> hyperactive glutamate system that persist after alcohol consumption ceases –> drug prevents relapse to alcohol drinking

Question 10

antiepileptic that can be used to treat alcoholism but not FDA approved and its mechanism

Answer 10

Topiramate –> decreases mesolimbic dopamine release after alcohol and decreases craving

Question 11

what are benzos commonly used to treat

Answer 11

insomnia and anxiety disorders

Question 12

describe benzos and barbiturates in term of physical dependence and addiction

Answer 12

both can lead to physical dependence but vary rarely addiction

Question 13

what are the psychostimulants

Answer 13

Cocaine
Amphetamine
Methylxanthines

Question 14

what are examples of methylxanthines

Answer 14

Caffeine
Theophylline
Theobromine

found in coffee, tea, chocolate, soda

Question 15

mechanism of action of methylxanthines

Answer 15

block adenosine receptors –> removing the inhibition of NE release –> act as stimulant

also adenosine promotes sleep and drowsiness so blocking it leads to insomnia and alertness

stimulate secretion of HCl –> so not to be used if one has peptic ulcers

Question 16

uses of methylxanthines

Answer 16

Theophylline is used in chronic asthma

Caffeine and ergotamine for migraine

Question 17

what is the lethal dose of caffeine and what does it lead to

Answer 17

10g of caffeine which is about 100 cups –> arrhythmias

Question 18

mechanism of cocaine

Answer 18

inhibits reuptake of dopamine, NE, and serotonin

Question 19

how do you identify a user of cocaine

Answer 19

presence of benzoylecgonine in urine

Question 20

mechanism of amphetamine (derivates are methamphetamine and methylphenidate)

Answer 20

• increases release of catecholamine neurotransmitters including dopamine
• weak MAOI

behavioral effects similar to cocaine

Question 21

uses of amphetamines

Answer 21

Attention Deficit Syndrome (ADHD)

Narcolepsy

Question 22

mechanism of action of nicotine

Answer 22

selective full agonist of nicotinic receptors –> involves ventral tegmental area where nicotinic receptors are expressed on dopamine neurons

Question 23

FDA approved treatment for cessation of smoking

Answer 23

Nicotine Replacement Therapy
Buproprion
Varenicline

Question 24

mechanism and AE of varenicline

Answer 24

• partial agonist at neuronal nicotinic acetylcholine receptors in the CNS
• suicidal thoughts, mood changes, vivid nightmares

Question 25

most commonly abused opioids

Answer 25

heroin, morphine, codeine, oxycodone among health care professionals: meperidine and fentanyl

Question 26

drugs used for opioid withdrawal (separate based on classes)

Answer 26

opioid agonists: Methadone and Buprenorphine alpha 2 agonists: clonidine and lofexidine opioid antagonist: naltrexone

Question 27

produces most of the pharmacological effects of smoked marijuana

Answer 27

THC - Tetrahydrocannabinol (Dronabinol)

Question 28

mechanism of marijuana

Answer 28

works via Gi --> inhibits adenylyl cyclase, open K channels, close Ca channels

Question 29

AE of THC

Answer 29

increased HR, decreased BP, reddening of conjunctiva

Question 30

uses of therapeutic THC -- dronabinol

Answer 30

- Anorexia associated with weight loss in AIDs patients | - nausea and vomiting seen in cancer chemo patients

Question 31

what are the psychedelic agents

Answer 31

``` LSD Mescaline Phencyclidine (PCP) Psilocybin MDMA ```

Question 32

mechanism of action of hallucinogens (LSDs)

Answer 32

agonistic effects of 5-HT2 receptors in the CNS --> psychomimetic symptoms (hallucinations) and sympathomimetic symptoms (mydriasis, hypertension, tachycardia, flushing, sweating etc)

Question 33

AE of LSD

Answer 33

bad trips -- severe agitation

Question 34

mechanism and clinical features seen in PCP

Answer 34

competitive antagonist of NMDA receptors --> NYSTAGMUS while awake and agitated, violent or bizarre behavior, miosis, anesthesia, analgesia, hypertension,

Question 35

what is used to treat the extreme violent psychotic behavior seen in use of PCP

Answer 35

benzos

Question 36

mechanism and clinical features of MDMA (ecstasy)

Answer 36

increases concentration serotonin in synaptic cleft by working on serotonin transporter --> tachycardia, muscle aches, agitation, hyperthermia, and seizures

Question 37

what are the inhalants

Answer 37

Volatile Organic Solvents (paint thinners etc) Organic nitrites Nitrous Oxide

Question 38

use of nitrous oxide

Answer 38

intoxicant used by medical personnel that causes euphoria and analgesia before loss of consciousness usually 35% N2O mixed with O2

Question 39

what happens if given 100% nitrous oxide

Answer 39

asphyxia and death

Question 40

name the organic nitrite and its use

Answer 40

Amyl nitrite -- treatment of angina

Question 41

what are anabolic steroids used for

Answer 41

increase muscle mass and definition