Antidepressant Classes
SSRI SNRI TCA MAOi others: mirtazapine, buproprion, trazadone Atypical Antipsychotics
SSRI:
First line tx for depressive disorders.
Med:
MOA:
block reuptake of serotonin, increasnig the serotonin in the synaptic cleft and down regulating 5HT1A receptors on post synaptic neuron, so less inhibition of that neuron leading to more firing and increased serotonin release.
*efficacy of all of these drugs is the same, its the half life and SE that differ.
SSRI
Longest: Prozac up to 3 days, shortest is Luvox 15hrs
Citalopram (Celexa) Escitalopram (lexapro)
Use caution with:
MAOis are CI if taking within 2wks d/t risk of serotonin syndrome.
SSRI:
SE:
Withdrawal:
Fluvoxamine (Luvox) and Paroxetine (Paxil) are more likely to have withdrawal sx d/t such short half lives.
4-6wks
Admin:
-QD dosing, if makes sleepy take at night, if insomnia take in AM
-duration of thearpy is lifelong, if you d/c the med make sure to continue it for 1 yr after resolution of sx for recurrence of severe depressive episode.
Which SSRI has least problems with wt gain? Most wt gain?
Which SSRI is most likely to cause diarrhea?
T/F SSRI increase the risk of abnormal bleeding?
Least prob w/ weight gain = prozac.
Most wt gain = Paxil
Diarrhea = Zoloft
True, they inhibit platelet function. ..also they increase bone fxs..
SNRI
Meds:
-act on Serotonin and NE
MOA: inhibit reuptake of NE and serotonin, acts same as SSRI otherwise.
Use as 2nd line therapy if unable to use SSRI.
Taking these with food will decrease the rate of absorption but not the degree of absorption.
SNRI:
-SE
SE:
Pristiq
-MC SE
Cymbalta:
Effexor:
Pristiq SE: nausea, HTN
Cymbalta:
-CI: uncontrolled angle closure glaucoma, severe or renal or liver impairment.
Indicated: diabetic neuropathy and fibromyalgia
SE: weight gain!!!!
Effexor:
TCAs:
Tertiary amines:
2ndry amines:
No, try to avoid them.
MOA: inhibit reuptake of serotonin and NE.
Half life 24hrs
Cardiac SE:
-heart block, ventricular arrhythmias, sudden death
TCAs
-SE
SE:
MAOi’s
Meds: Phenelzine (Nardil) Tranylcypromine (Parnate)
Dangerous: drug-drug interactions, dietary restrictions, HTN crisis, serotonin syndrome.
Other meds used in tx of depression
Trazodone (desyrel) Bupropion (Wellbutrin) Mirtazapine (remeron) Vilazodone (Viibryd) Vortioxetine (Brintellix)
Trazodone
Wellbutrin:
Low dose = sleep
high dose = antidepressant
SE: sedation, orthostasis, priapism (prolonged erection)
Wellbutrin:
Avoid with bulemia and may lower seizure threshold.
SE: no sexual SE.
Mirtazapien (Remeron)
MOA: blocks adrenergic receptors leading to increased release of NE and serotonin.
SE: sedation, weight gain (good for elderly), less sexual SE, good for pts with nausea.
Serotonin Syndrome:
What; constellation of sx caused by excess of serotonin, ranges from mild to fatal.
Cause;
Drugs:
Psych meds: any of them.
Pain meds: demerol, tramadol, fentanyl
Migraine meds: triptans
Neurology: levodopa, carbipoda-levodopa, valproate, carbamezepine
OTC: tobitussin
Anti-emetics: zofran
Street drugs: cocaine, meth
ADHD; amphetamine derivatives, dexxtroamphetamine
Serotonin Syndrome:
onset: usually rapid onset, present within 24hrs and most within 6hrs of change in dose or initiation of a drug.
PE:
HARM = hyperthermia, autonomic instability (delirium), rigidity, myoclonus (tremor/muscle spasm)
-ocular clonus, tremor, dilated pupils,
Signs and Sx:
What is the Hunter criteria for serotonin syndrome?
Has taken a serotonergi agent PLUS(1):
KNOW THIS!
Tx serotonin syndrome
How long until sx resolution?
first line is D/C serotonergic agents
Often resolves within 24hrs of d/c serotonergi agent.
*MAOis carry the greatest risk of this and sx can persist for several days!
Seasonal Affective Disorder:
MC in northern hemisphere
Sx completely mimic depression but have cyclical pattern.
Tx: UV light