Anti-psychotics and mood-stabilizing drugs Flashcards
Schizophrenia
- positive symptoms (4)
- negative symptoms (4)
- mood symptoms (4)
- delusions, hallucinations, catatonia, disorganized speech
- alogia, avolition, anhedonia, social withdrawal
- depression, anxiety, suicidality, hopelessness
Dopamine pathways - Schizophrenia
- Meso-cortical tract –> mood, cognition = negative symptoms
- Meso-limbic tract –> anti-psychotic effects = positive symptoms
- Tubero-infundibular tract –> prolactin elevation
- Nigrostriatal tract –> movement disorders
Pathogenesis of Schizophrenia
-dopamine –> found mainly in the diencephalon and the substantia nigra of mid-brain
-Dopamine hypothesis:
low dopamine in neurons at the pre-frontal lobe –> negative symptoms
increase dopamine at central structures –> positive symptoms
Anti-psychotic drugs classification
- Typical (“first generation”) - chlorpromazine and haloperidol –> block D2 receptors, hardly act on negative symptoms
- Atypical (“second generation”) - clozapine, risperidone, olanzapine, quetiapine, arizipiprazole –> block D2 and 5-HT receptors, act on positive and negative symptoms
Extra-pyramidal side effects
- results from D2 receptors blockade in the nigrostriatal pathway
- one of the main disadvantages of 1st generation drugs
- less severe in atypical
Acute dystonia - involuntary movements (muscle spasms, restlessness, protuding tongue), can happen straight after taking the medicine, after discontinuation there are no symptoms
Tardive dyskinesia - develops after months or years, often irreversible, gets worse when anti-psychotic therapy is stopped and is resistant to treatment, involuntary movements of face and tongue (also trunk and limbs)
Anti-psychotic drugs
-side effects (4)
- all cause discontinuation and weight gain
- extra-pyramidal side effects
- anti-psychotic malignant syndrome
- hyper-prolactinemia
Clinical consequences of hyper-prolactinemia (4)
- sexual dysfunction
- breast pathology
- reproductive dysfunction
- hypogonadism
Where are D2 receptors mainly located?
Meso-limbic tract
Most efficient drug anti-psychotic drug?
Clozapine, but it is not always used because of very dangerous side effects –> causes agranulocytosis
Thoughts of mania and depression
Mania –> everything is great, i can do anything, no limitations,
Depression –> opposite
Mood-stabilizing drugs
-classes of medications
Mood stabilizers: relief acute mood symptoms and prevent recurrence of episodes of both poles (depression and mania) –> lithium, anti-convulsants, anti-psychotics
Anti-depressants: used in combinations with mood stabilizers because if used alone it may exacerbate manic symptoms
Anxiolytics: calm an episode of mania and relief anxiety
Lithium
- advantages (2)
- disadvantages (3)
-“gold standard” (low cost, long experience), acute and maintenance (prevents relapse)
- slow onset of action (1-4weeks)
- high number of non-responders
- narrow therapeutic index
Lithium
-side effects (5)
- nausea, vomiting, diarrhea
- cerebellar effects
- weight again
- thyroid dysfunction
- cognitive impairment
Lithium
-mechanism of action (5)
- inhibition of inositol triphosphate formation
- inhibition of glycogen synthase kinase
- inhibition hormone- induced cAMP production
- blocks cellular responses
- blocks many receptors mediated effects
Carbamazepine and valproic acid
used for prophylaxis and treatment of manic episodes in patients unresponsive to lithium
