Psychopharm Concepts Flashcards
Efficacy vs Effectiveness
Efficacy is controlled setting. Effectiveness is real world with missed doses.
When antacid pops up in the vignette?
They are trying to cue you in that something is impairing/changing the absorption.
Do children have more or less total body water than adults?
More total body water, less fat. They will have increased volume of distribution for water soluble drugs .
What is Phase I metabolism?
Adding a ‘handle’ on the drug mostly through CYP450. This means oxidation, reduction, or hydrolysis.
3A4 inhibitors?
Ketoconazole, grapefruit juice, erythyromycin , cimetidine, nifedipine, verapamil
What all drugs will carbamazepine induce?
depakote, haldol, OCP, protease inhibitors, midazolam, vincristine.
What enzyme does smoking induced
1A2 (the 1 looks like a cigarette). This will impact imipramine, clomipramine, luvox, trazdoone, thiothixine, haldol, fluphenazine, olanzapine, xanax, valium
Phase II Metabolism
Conjugation of drug with endogenous substrates (glucuronic acid, glutathione, sulfate, acettie.
- Glucuronides are excreted into bile while all others go into urine.
What does ‘Out the Liver Mean?’
Drugs that go directly to Phase II metabolism. (Oxazepam, temaepam, lorazepam, Lamictal).
How does remeron get its antidepressant effects?
Via alpha 2 antagonism which is a negative feedback loop. Ultimately increases level of monoamines.
What is an example of an inverse agonist?
Pimavanserin (nuplazid)
How are remeron and clonidine/guanfacine opposites?
Remeron is alpha 1 and alpha 2 antagonism
Clonidine is alpha 2 agonism.
How do the triptans work?
Constrict cranial arteries. Mechanism is that they are 5-HT1D agonists.
What makes aripiprazole unique?
It is an antipsychotic that is a partial agonist at 5HT2a and D2.
What are the 3 subgroups of monoamines?
1) Catecholamines (catechol group: NE, E, D)
2) Tryptamines (serotonin, melatonin)
3) Histamines
What cardiac problems can lithium cause?
Supraventricular arrythmias suh as sick sinus syndrome and tachy-brady syndrome. Can prolong PR interval.
Which med may SHORTEN QTc?
bupropion
Which 3 antipsychotics are the most likely to cause hypotension/falls?
Clozapine, seroquel, and chlorpromazine
Two main drugs to avoid in renal disease?
Lithium and duloxetine
In addition to the NTD, what other defects can depakote cause to baby?
Neurobehavioral teratogenicity: lower IQ, possible ID, and linked to autism. Can also have withdrawal sx, liver toicity, and hypoglycemia.
BZD and risk to baby
Cleft abnormalities can happen along with floppy baby syndrome if given right before birth.
Is doxepin safe for lactation?
No, it is the worst. L5 category.
What should you counsel anyone when giving luvox?
Caution on caffeine consumption. Luvox inhibits CYP1A2 metabolism of caffeine. Pt can develop caffeine intoxication including palpitations, anxiety, insomnia, dyspepsia, and loose stools.
Which carbamazepine interactions should one be aware of?
- erythrymocyin leads to carbamazepine toxicity
- Lowers valproate
- Lowers OCP, increased risk of pregnancy.
Common luvox interactions
- Warfarin toxicity
- Theophylline toxicity
- Clozapine toxicity
- Caffeine toxicity
Linezolid interactions
Antibiotic with MAOI activity, can lead to serotonin syndrome.
Methylene blue
Can lead to serotonin syndrome.
What is significant about ST. John’s Wort?
3A4 inducer which can decrease the plasma levels of OCP, increasing risk of pregnancy. Pharmacodynamically, it can combine with fluoxetine to cause serotonin syndrome.
What does grapefruit inhibit?
3A4 inhibitor. Separating ingestion of grapefruit from drug does not work bc cell neds 24 hours to replace 50% of inactivated 3A4 enzyme.
Buspar and grapefruit
Grapefruit can have 9x increase area under curve of buspar, vastly increased concentrations.
Cannabidiol and CYP
3A4 inhibitor which could increase bzd and opioid levels
PPI interactions
PPI’s cause 2C19 inhibition which increases levels of citalopram, escitalopram, and diazepam.
Cimetidine interactions
3A4 inhibitor that can increase chlordiazepoxide, dizepam, some tca, and citalopram.
Amphetamines and GERD meds
Increased pH leads to increased meth absorption. ADHD meds would get increased too
Does volume of distribution go up or down in the elderly?
Up if it is a lipid soluble drug.
OCP and caffeine
OCPs reduce the elimination of caffeine
Main reasons for noncompliance
Cost of medications are too high
Psychiatric symptoms interfere with treatment
Instructions are poorly given
In addition to NTD, what other things happen if uterus is exposed to VPA?
increased risk of autism
What percentage of white people are poor CYP2D6 metabolizers?
6% to 10% , lower in Asians (2%).
chlorpromazine associated with high or low EPS?
Low
MOA of bzd on GABA receptor
MODULATOR
Black box warning for carbamazepine?
Derm rxn
LSD mechanism of action?
5-hydroxytryptamine receptor agonism. strong serotonergic effects
Which 2 vitamins have evidence for tardive?
Vitamin E and Vitamin B6 (pyridoxine)
What electrolyte abnormality does oxcarbazepine cause?
Hyponatremia like SSRI’s.
Which meds can lead to diabetic ketoacidosis?
atypical antipsychotics because they disrupt metabolism
Which 2 TCA’s have the lowest anticholinergic profile?
nortriptyline and desipramine.
VPA can lead to what in females?
PCOS
Paralytic ileus is seen in what?
clozapine toxicity
Narrow angle glaucoma, be careful about which med?
Benztropine
What receptor does buspar work on?
5HT1A receptor
What antipsychotic should be avoided in breastfeeding?
Clozapine. Agranulocytosis
What is the amino acid precursor of all the catecholamine neurotransmitters including dopamine, norepinephrine, and epinephrine.
Tyrosine
What medicine, when combined with haldol, can cause a syndrome that looks like NMS?
Lithium
How do you treat lithium induced NDI?
lithium-induced NDI is amiloride, a potassium-sparing diuretic that reduces lithium uptake in the cells of the collecting duct improving responsiveness to ADH-stimulated translocation of AQP2 to the membrane of the principal cells.
Common 1A2
fluvoxamine, haldol, theophylline
Psychogenic polydipsia more common in typical or atypical antipsychotics?
typical. Switch them to an atypical .
What should one worry about with wellbutrin and drug interactions?
2D6 inhibitor. Gonna crank up things like nortriptyline.
Which 4 antipsychotics require renal adjustment?
clozapine, paliperidone, risperidone, and lurasidone
What are platelet serotonin levels doing during the headache phase of a migraine? Urine platelet serotonin levels?
Drop dramatically during the headache phase of migraine, while levels in the urine increase
What types of molecules can go through the blood brain barrier?
the blood-brain barrier (BBB) allows lipophilic molecules to cross easily by passive diffusion, which is the reason for the acute effects of CNS depression after solvent inhalation.
Other than trazodone, what other drugs can cause priapism?
Antipsychotics
First line treatment for predatory aggression?
antipsychotics
What drugs are used for myoclonus?
Clonazepam and valproic acid are most commonly used for myoclonus, though often with limited efficacy.
What dietary counseling should you tell pt’s regarding Z drugs?
No fatty meals.
Caffeine intoxication causing heart problems, what do you do?
hemodialysis
Safest antipsychotic for pregnancy?
Olanzapine
Which 2 drugs can help reduce bedwetting?
desmopressin and imipramine.
Dutasteride have what teratogenic effect?
Birth defects in male fetuses
Which neurotransmitter does MAO B have a higher affinity for?
Dopamine , causing its degredation
If lymphadenopathy is present after a lamictal rash, is it benign or not benign?
Not benign.
Bupropion MOA
Bupropion is a norepinephrine-dopamine reuptake inhibitor (NDRI) that inhibits the reuptake of dopamine and , to a lesser degree, norepinephrine, leading to an increased level of these chemicals in the synapse.
Drugs to treat the 4 types of aggression:
affective, organic, predatory, and ictal
The drug of choice for organic-like aggression is imipramine, which is a tricyclic antidepressant. Anticonvulsants are a valid alternative. Selective serotonin reuptake inhibitors may have some clinical utility as well. Lithium is a drug of choice for affective aggression. Haloperidol might be an acceptable choice for predatory aggression, however second-generation antipsychotics are less neurotoxic and should be considered first.
Which antiepileptic causes aplastic anemia and liver failure , therefore is a last resort?
Felbamate
Which NT abnormality is associated with episodic violence?
An increased norepinephrine receptor sensitivity is associated with hyperactivity to the environment which may increase the likelihood of aggression.
False Positive for amphetamines and methamphetamines
bupropion
Excitatory NTs?
Inhibitory NTS?
Glutamate and aspartate are the amino acids that serve as excitatory neurotransmitters and activate the N-methyl-d-aspartate (NMDA) receptors which have been implicated in learning, memory and mood changes.
What is amoxapine used to treat?
Depression
Who is most susceptible to acute dystonic reactions?
Young, antipsychotic-naive males are more prone to acute dystonic reactions.
What do you give for lithium induced NDI?
Amiloride
