Psychopharm Flashcards
CYP3a4 inducers
Carbamazepine, phenytoin, oxcarbmazepine
drugs with increased risk of depression
oral contraceptinves, resperine, clonidine, levodopa, alcohol, hydralazine, amantadine, benzos, guanethidine
benefits of high potency antipsychotics in pregnancy
decreased risk of neonatal hypotension, anticholinergic, antihistaminic.
MAOI SE
pyridoxine deficiency
sexual SEs, WG
mechanism of sexual SEs in antipsychotics
ANTIADRENERGIC
alpha 1 receptor effects, cholinergic antagonism,
dopamine blockade decreases sexual arousal.
risks of lithium exposure during pregnancy
arrythmias, polyhydramnios, floppy infant syndrome, premature delivery
levels can become toxic due to shifting fluid levels.
draw lithium levels weekly beginning at 34 weeks
enzyme that metabolizes methylphenidate
CES1A1
st. johns wart
CYP inducer, lowers levels of drugs (warfarin, digoxin), ; also acts as SSRI; avoid with MAOs and SSRIs.
donepezil
REVERSIBLE ACH esterase inhibitor; SEs of GI upset
carbemazepine
blocks Na+ channels;
inhibits voltage dependent sodium channels and presynaptic sodium channels
effect on sodium channels result in inhibition of glutamate release.
p450 3A4; absorption is increased by food, can cause beningn neuropenia, rare agranulocytosis,
cyp2d6 inhibitors
wellbutrin, duloxetine, fluoxetine, paroxetine, zoloft, rotanivir, cemitidine
CYP2D6 inducers
rifampin, dexamethasone
PCOS and depakote
PCOS is a SE of depakote, increased risk of SAs.
10% of females develop PCOS every year.
lithium and the kidneys
causes impaired concentrating capacity by reducing ADH.
LOW SALT diet is likely to increase lithium
can cause nephrogenic diabetes inspidus (increased water output in urine) = hypernatremia; competes with ADH receptors; can use amiloride to reduce
CAN MANAGE polyuria and polydipsia with one single bedttime dose, can use thiazide diuretic or amiloride.
10-20% of people on lithium for over 10 years will have renal changes.
lithium and insulin
lithium has an insulin like effect: lowers BG, increases appetite and WG
associated with clozapine
myocarditis, eosinophilic colitis, neutropenia
antipsychotics that increase risk of seizures
clozapine (4% > 600mg), chlorpromazine is MC in causing seizures
6 P450 enzymes that are responsible for 70-80% of all drug metabolism
1A2, 2C9, 2C19, 2D6, 3A4, 3A5
clozapine mechanism
dopamine, serotonin, alpha receptor antagonist
abilify mechanism
serotonin 5HT1A partial agonist, partial dopamine agonist
antagonist at 5ht2 receptor
NOT D2 blocker!!!
atomoxetine
selective norepi reuptake inhibitor.
blocks reuptake of norepinephrine
SEs: WL, abdominal pain, decreased appetite, vomiting, nausea, headache, dizziness, fatigue, irritability
SEs worse in slow metabolizers.
Lithium induced hypothyroidism
MC in women. Need TFTs, EKG, and BMP before starting in pts older than 40. Order renal fucntion test q 3 months and TFT once in 1st 6 months. After 6 mo, order BUB, CR and TFTs q 6-12 months.
usually occurs in 1st 6-18 mo
Hypothyroidism is NOT a CI, treat with levothyroixine
Hypothyroidism associated with rapid cycling and increased depression
MAOs
sexual SEs and weight gain ie. phenelzine
SE of chlorpromazine
mild pigmentary changes in retina (large doses)
thioridazine also causes irreversible pigmentary retinopathy in large amounts
Mirtazapine drug class
tetracyclic antidepressant. noradrenergic and specific serotenergic antidepressant.
alpha 2 adrenergic receptor antagonist,
serotonin 5h2 antagonist
Blocks presynaptic alpha 2 adrenergic receptor, which results in 5-HT-1A activation and increases release of dopamine. 5HT2 antagonist
antidepressant not metabolized by p450
desvenlafaxine
CYP enzyme present at birth
3A7
CYP 3A4 inihibitors
amiodarone, anastrozole, azithromycin, cannabinoids, cimetidine, clarithromycine, clotrimazole, cyclosporine, danazol, delavirdine, diethyldithiocarbamate, diltiazem, dirithromycine, disulfram, entacapone, erythromycin, ethinyl estradiol, fluconazole, fluoxetine, ketoconazole, metronidazole, nefazodone, paroxetine, ranitidine, sertraline, ritonavir, depakote
galantamine
competitive inhibitor of aceytylcholinesterase; allosteric modulator of nicotinic acetylcholine receptors
SE GI disturbance
SEs of ACHesterase inhibitors
PARASYMPATHETIC/LEAKY
n/v, diarrhea, bradyicardia, hypotension, hypersecretion, bronchoconstriction, GI hypermotility, decreased intraocular pressure
MC clozapine SEs
sedation (20-50%)
sialorrhea/drooling (10-40%c)
sumatriptan
5-Ht1D and 5-HT1B agonist
Topimax and ETOH
antagonizes glutamate and suppresses alcohol induced dopamine release
SSRI with greatest WG
Paroxetine
SSRI that increases clozaril levels
Fluvoxamine
fluvox also inhibits 3A3/4 which increases xanex, triazolam, trazodone
Meds not safe to use with MAOIs
meperidine, epinephrine, loacl anesthetics and decongestants … can cause hypertensive crisis
Anticholinergic Side effects
result from muscarinic cholinergic receptors.
blurred vision, constipation, dry mouth, urinary retention;
tachycardia, ocular crisis in patients with narrow angle glaucoma, confusion, delirium
also ED and impaired vaginal lubcrication (TCA’s MAOIs)
tricyclic antidepressants block muscarinic ACH receptors
Risks of duloxetine
increases hepatic transanimases and may inc levels in patients with liver dz
mood stabilizer that slows cardiac conduction
carbamazepine
avoid in pts with high grade atrioventricular block and sick sinus syndrome
primary OD sx in Clozapine
delirium, lethargy, tachycardia, hypotension, respiratory failure
increases warfarin levels
SSRIs
effect of valproate on lamictal’s metabolism
valproate doubles half life. Will have to halve starting dose.
modafinil
has histaminergic mechanism in addition to increasing dopamine by binding to transporter.
dopamine reuptake inhibitor
Topimax MOA
inhibits NA+ channels, enhances GABA-a receptors, antagonizes subtype of glutamate receptors
antagonizes kainate and AMPA receptors
1% get stones, metabolic acidosis
associated with acute myopia and secondary closure glaucoma , causing ocular pain andd blurred vision.
MAO-A vs. MAO-B
MAO-A breaks down tyramine
Memantine
glutamatergic NMDA Receptor Antagonist
Varenicline MOA
Alpha 4 beta 2 nicotininc acetylcholine receptor partial agonist
antipsychotics with highest anticholinergic effects
cloazpine, thioridazine, chlorpromazine
where melatonin is produced
pineal gland
kava kava
acts on GABA receptors, long term use linked to liver toxicity. Used for sedative and anesthetic qualities
Ketamine
NMDA receptor antagonist; acts at opiod recepters and monoamine transporters; hallucinogen and is similar to PCP
dissociative hallucinogen
Xyrem
sodium salt of gamma-hydroxybutyric acid (GHB); treats cataplexy associated with narcolepsy.
agonizes GABA-b receptor complex and GHB receptor
sertraline and CYP2D6
sertraline at 200mg is an inhibitor of CYP2D6 and increases levels of tramadol
disulfram
blocks dopamine beta hydroxylase in brain
lithium
Acute: tremor, polyuria, polydipsia, cognitive problems, poor memory and concentration, GI distress, benign leukocytosis, acne and edema.
Chronic: hair loss, weight gain, possible kidney damage, thyroid disfunction,
EKG: changes in repolarization phase, worsening existing arrhythmias and (less commonly) inducing new ones.
reduces effect of ADH on kidney
associated with hyperplasia and adenomas of parathyroid glands
Topimax 200mg or more
interferes with OCPs
treat lithium induced polyuria
HCTZ or amiloride(K+ sparing)
depakote in mania
increases GABA
superior to lithium in mixed sx
superior to lithium in patients with prominent depressive sx during mania or with multiple prior mood episodes
less effective than olanzapine for acute mania
response rates: 48-53%
depakote increased GABA in the brain
selegiline
irreversible MAO-B inhibitor
Contraindicated in pheochromocytoma and surgery- excess norepinephrine can lead to hypertensive crisis
used to target PD sx by increasing levels of dopamine
SSRIs in bleeding
cause dec platelet activation due to reduction of serotnin in platelets. No serotonin in platelets impairs ability of platelets to aggregate.
risk of bleeding is similar to NSAIDs