Antidepressants for Manic Disorders - Lichtblau Flashcards
What is unipolar vs bipolar disorder?
Unipolar depression may occur…
- Once
- Recurrent episodes, separated by periods of euthymia
Bipolar mood disorder patients alternate between
- Depression
- Mania
- Brief euthymia
What is euthymia?
“normal” mood behavior
Why should you never give an SSRI by itself to a patient with bipolar disorder?
May cause rapid onset of mania!
They should be on mood stabilizer therapy so this doesn’t happen
What two drugs CAN you give as MONOtherapy for bipolar depression?
Hint: we’re not talking about mood stabilizer, these are just for the depression part
Lurasidone (atypical antipsychotic)
Vortioxetine
What is a major reason that some antidepressants may be taking 2-3 weeks to be effective?
It could be that we are affecting the pathway in in the very beginning rather than switching things up toward the end of the path. Maybe faster-acting drugs like ketamine are a little later in path
What does the amine hypothesis of modd disorders say?
levels of amine neurotransmitters are requited for normal mood
- NE
- 5HT
Depression: receptors insensitive, or amine problems
Mania: excess of NT
How do tricyclic antidepressants work?
They block reuptake of 5-HT and/or NE at nerve terminals
You need to know one TCA that is NE-slective and one that is mixed NE/5HT.
Name them!
NE
Desipramine
NE/5HT
Imipramine
What is the effect of TCA’s on normal individuals?
Depressed individuals?
Normal - no effect on mood - dry mouth, urinary retention, blurred vision Depressed -Elevate mood in 2-3 weeks -50% dry mouth and tachycardia
Despite elevated NE, TCA’s can give you orthostatic hypotension. How is that possible?
One of TCA’s actions is to block alpha-1 receptors. These receptors are on the vasculature. When you stand up and your baroreceptors go off its not going to have the same effect on your arterioles to boost BP because the receptors are blocked already.
Why don’t you give a very depressed patientmore than one week’s supply of TCA’s?
They have a low therapeutic index. If they are suicidal they can easily overdose if they have a large supply.
Does TCA have any important drug-drug interactions?
Strengthens effect of other CNS depressants:
-alcohol, opioids, anxiolytic/sedatives/hypnotics
What MAO inhibitor drug do we need to know?
Phenelzine
Difference between MAO-a and MAO-b?
MAO-a: Metabolizes NE and 5HT in the brain and gut
MAO-b: Metabolizes DA in blood
What kind of drug interactions do you have to worry about with MAO inhibitors?
Tyramine
- a sympathomimetic amine that is usually completely metabolized by MAO
- built up Tyramine can cause huge release of catecholamines and cause a hypertensive crisis!
What SSRI’s are important to be familiar with?
Fluoxetine (Prozac)
Sertraline (Zoloft)
Citalopram (Celexa)
Escitalopram (Lexapro)
Adverse effects of SSRI’s?
- Nausea, diarrhea and weight loss
- anxiety, nervousness, insomnia
- Sexual dysfunction
- Suicidality in the young
Mechanism of action of SSRI’s?
What specifically creates the improvments?
- Selective inhibtion of serotonin by CNS neurons
- 5HT2a may be where you see clinical improvement
What is an autoreceptor?
What is a heteroreceptor?
Auto - Presynpatic neuron releases neurotransmitter and that NT acts on the presynaptic neuron itself to affect release of that same NT
Hetero - NT from neighboring synapse can act on this type of receptor to alter that neighbor’s release of a different NT
What are the two SNRI’s you should know?
Venlafaxine
Desvenlafaxine
How does vanlafaxine work?
It blocks serotonin and noreprinephrine reuptake
Why is it that increasing the dose of venlafaxine improves its efficacy when this isn’t the case with other antidepressants?
Apparently venlafaxine actually affects different monoamines depending on the dosage.
- low dose - only 5HT
- more - 5HT/NE
- MORE - 5HT/NE/DA
So what is the deal with devenlafaxine?
It the active metabolite of venlafaxine (SNRI)
How does Buproprion work?
Adverse effects?
- Increases NE and DA transport
- Adverse effects come from stimulation (agitation, anorexia, insomnia)
How does ketamine work? What kind of drug is it?
Adverse effects?
It is an NMDA receptor antagonist
It is an injectable anesthetic, but helps depression too
Adverse effects: nightmares/hallucinations
What is lithium carbonate used for?
Treating bipolar disorder
A patient who says they are on some sort of meds for bipolar comes in to the ER. They have a very abnormal BUN and creatine levels. What is going on?
Lithium carbonate competes with Na for reabsorption in the kidney
- Means that sodium deficiency increases lithium toxicity
- can lead to kidney failure
Some normal side effects of Lithium carbonate?
- Fatigue, muscle weakness, slurred speech, ataxia, fine hand tremor
- excessive thirst and urination
What is valproic acid (depanken/depacon) used for?
Good for non-rapid cycling bipolar
Great for rapid cycling bipolar
Works better for manic episodes rather than long-term management.
What is carbamezapine used for?
Prophylaxis of bipolar disorder
What kind of drug is quietiapine?
It’s an atypical antipsychotic
Whar kind of drug is valproic acid?
its actually an anti-convulsant… interesting
Lurasidone is what kind of drug?
Atypical antipscyhotic for bipolar disorder treatment
