Pharmacology of drug abuse Flashcards
(44 cards)
what are the 7 classes of drugs Abuse ?
1) Opoids – morphine and codeine etc
2) Sedative/Hypnotics
3) CNS stimulants
4) Cocaine
5) Cannabis
6) Hallucinogens
7) MISCELLANEOUS
what is Abstince syndrome ?
a term used to describe the signs and symptoms that occur on withdrawal of a drug in a dependent person
what is dependance ?
a state characterized by signs and symptoms frequently the opposite of those caused by a drug, when its withdrawn from chronic use or when the dose is abruptly lowered
mechanism of Dependance :
1- Drugs of abuse induce amplified dopamine release and activate the same synaptic adaptations as natural re-inforcers.
2- increase glutamate receptors
3- increased structural protein expression
4- increased dendritic spine size
what can induce relapse to drug-taking behavior ?
- Stress ( by increasing release of dopamine)
2. Exposure to drug-related sensory cues ( increased release of Glutamate and it receptor
what is the mechanism of action of cocaine ?
inhibits dopamine reuptake transporters (DAT), resulting in increased synaptic dopamine levels and increased postsynaptic dopamine receptor activation at synapses in the Nucleus accumbens
what is the consequences of increased postsynaptic dopamine receptor ?
result in D2 autoreceptor activation, which decreases dopamine synthesis
what is the mechanism of action of Amphetamine ?
- release of endogenous catecholamine from nerve endings
- inhibit neurotransmitter reuptake into vesicles
these combined actions cause neurotransmitter concentrations to increase in the synaptic cleft. - DAT expression increases (thus reduce dopamine synthesis )
what are the initial symptoms of Amphetamine overuse?
mood elevation and euphoria, increased energy and alertness & with time stereotyped behavior emerges, including hyperirritability, jumpiness, grinding and rashing of the teeth, touching and picking of the face and extremities, suspicious
what are the S&S of Cocaine acute intoxication ?
Hyperfunction, high BP, tachycardia, pupillary dilation, motor unrest, sweating and chills, convulsion
what are the S&S of Cocaine chronic intoxication ?
paranoid psychosis similar to paranoid schizophrenia, High risk for arrhythmia and CVS diseases
Vasoconstriction results in tissue necrosis (with intranasal use)
treatment of addiction :
- benzodiazepines, e.g. Diazepam in acute cases.
what drugs are not recommended In acute cases?
antipsychotic drugs: e.g. Chlorpromazine or Haloperidol;
barbiturates and diazepam
what is the treatment for chronic abusers ?
Desipramine (tricyclic antidepressants)
what mood stabilizers is effective in case of Euphoria?
Lithium
what are some examples of Hallucinogens ?
Lysergic acid diethyl amide (LSD) , dimethyltryptamine (DMT), and diethyltryptamine (DET), psilocybin, psilocin
what is the mechanism of action of Hallucinogens ?
repression of central serotonin neuronal activity, and/or reduction in serotonin increases hallucinogenic potency of LSD.
what are the effects of LSD ?
Euphoric or dysphoric “trips”
tolerance and dependance of hallucinogens :
No intense physical dependence no withdrawal symptoms
what is the prominent feature of hallucinogens?
Changes in sensory perception (Time sense is lost)
what is the treatment for the psychotic and visual hallucinations episodes ?
phenothiazines
what is the treatment For psychotic episodes which last from several days to several months and resembles schizophrenia ?
Large doses of chlorpromazine
treatment for Acute hallucinogens intoxication :
Relaxing room is the only needed treatment.
what is PCP mechanism of action ?
non- competitive antagonist at NMDA-glutamate receptor and Inhibits dopamine uptake and enhances dopamine release
