Drugs Of Abuse- Pharm Flashcards
Define: Abstinence syndrome Addiction Dependency Withdrawal Tolerance Sensitization
Abstinence syndrome- s/s occurring w/ withdrawal of drug
Addiction- compulsive drug using behavior; use for satisfaction
Dependency- s/s oppo of those caused by drug when withdrawn from chronic use
Withdrawal- readaption of CNS to absence of drugs- evidence of physical dependence
Tolerance- dec response to drug
Sensitization- inc response w/ repetitive use of same dose
Dopamine Hypothesis of Addiction
What are the targets of the mesolimbic system
DA reward pathway- drug activates mesolimbic DA system leading to release of DA and pleasure
Mesolimbic targets- GPCR, ionotropic R, and monoamine transporters
Non-addicting drugs of abuse
- examples and explain
- explain long term effects
Non-addicting drugs of abuse
LSD/mescaline/psilocybin- repetitive exposure causes rapid tolerance/tachyphlyaxis; long term effects of LSD include flash backs
PCP/ketamine- NMDA antagonists used as gen asthetics; long term effects of PCP include irreversible schizo-like psychosis
GPCR Drugs of Abuse
- MOA
- examples
GPCR Drugs of Abuse
MOA- disinhibition of DA neurons
Examples- opioids, cannabinoids, and GHB/liquid X/date rape
Opioids
- how do they lead to addictive effects
- what are s/s of withdrawal
- how do you treat withdrawal
Opioids
- inhibit GABA inhibitor interneurons in VTA which disinhibits DA neurons leading to euphoria
- withdrawal- dysphoria, dilated pupils, piloerection, fever, rhinorrhea, lacrimation, yawn, NV, myalgia
- treat- naloxone (opioid antagonist that reverses effects in minutes but causes acute withdrawal syndrome) or methadone/buprenorphine (substitution therapy that can cause withdrawal syndrome if discontinued abruptly)
Cannabinoids
- how do they lead to addictive effects (what are the effects)
- withdrawal- s/s
- treatment
Cannabinoids
- THC disinhibits DA neurons via presynaptic inhibition of GABA neurons in VTA leading to euphoria, altered perception of time, hunger, anxiety, dec intraocular P, and pain relief
- mild and short lived withdrawal- restless, irritable, and insomnia
- treatment- dronabinol (THC analog used to treat anorexia and wt loss in pt w/ AIDS and chemo-NV) and nabilone (THC analog used to treat refractory NV in chemo)
GHB/Liquid X/Date Rape
-how does it lead to addictive effects and what are the effects
GHB
-activates GABAb-R on GABA and DA neurons leading to disinhibition of DA neurons causing euphoria, inc sensory perceptioin, social closeness, amnesia, and sedation
Ionotropic R Drugs of Abuse
-examples
Ionotropic R drugs of abuse
-nicotine, barbiturates, benzodiazepam, alcohol, inhalants
Nicotine
- MOA
- withdrawal
- treatment
Nicotine
- MOA- nAchR agonist at DA neurons in VTA
- withdrawal- irritation and sleeplessness
- treat- nicotine substitutes, buprorion (antidepressant), and varenicline (partial nAchR agonist prevents nicotine from stim mesolimbic system)
Inhalants
- MOA
- examples
- treatment
Inhalants
- MOA- inc excitability of VTA leading to euphoria
- ex- nitrates, ketones, aliphatics, aromatic hydrocarbons
- treatment- supportive
Biogenic Amine Drugs of Abuse
- examples of biogenic amine transporters
- examples
Biogenic Amine Drugs of Abuse
- transporters- DAT, NET, VMAT, SERT
- ex- cocaine, amphetamine, MDMA
Cocaine
- MOA- affects at VGNaC, DAT, NET
- acute effects
- OD
- risks w/ exposure
- reverse tolerance
- treatment
Cocaine
MOA- inhibit VGNaC and DAT to inc [DA] in nucleus accumbens and blocks NET to activate SNS (inc HR, BP, arrhythmias)
Acute effects- loss of appetite, hyperactive, insomnia
OD- hyperthermia, coma, death
Risks- inc risk of intracranial hemorrhage, stroke, MI, seizures
Reverse tolerance- sensitization to small doses
Treat- no antidotes; supportive care (propranolol for HR and diazepam for siezures)
Amphetamine
- MOA
- withdrawal
- treatment
Amphetamines
MOA- reverse action of biogenic amine transporters stim release of biogenic amines; neurotoxic
Withdrawal- dysphoria, drowsy, insomnia, irritable, depression
Treat- benzodiazepam
MDMA
- MOA
- heavy use leads to?
- acute effects
- withdrawal
MDMA
MOA- reverse action of biogenic amine transporters w/ preferential affinity to SERT which inc EC [serotonin]
Heavy use- long term cognitive impairment due to serotonin depletion
Acute- hyperthermia, dehydration, serotonin syndrome (mental status change, hyperactive autonomics, NM abnml), seizures
Withdrawal- mood offset w/ depression and aggression
