MDD—Monoamine hypothesis of depression, prescribing considerations- the theory is that depression is caused by a deficiency in monoamine
... [Show More] neurotransmission. And mania is the opposite - due to an excess of monoamine neurotransmission.
This hasn't really been proven yet, so then the focus shifted to the monoamine receptor hypothesis - that the abnormality of receptors for monoamine NTs cause depression. In that case, the lack of NT causes upregulation of receptors.
Also not proven yet. Right now the focus is on regulation of gene expression, growth factors, environmental factors, and epigenetic changes.
Prescribing considerations
- do not give antidepressants as monotherapy for bipolar - always combine with mood stabilizer. Must rule out mania or hypomania so don't confuse MDD with BPD and induce mania.
Monitor infant irritability when prescribe SNRI for breastfeeding.
Also keep in mind: client preference, prior treatment response, anticipated adverse effects, comorbidities, half life and interactions (if they will forget to take med, choose something longer acting), cost.
Start patient on drug for 4-8 weeks, on lowest recommended dose. If doesn't work, first increase dose, then switch to diff drug in same class and give adequate trial of high enough dose, then switch to a drug in a different class, then add a second med.
For older people - citalopram and escitalopram should be ½ dose, avoid paroxetine if have history of falls, avoid TCAs prescribed with out CNS depressants.
SSRIs what screens should be completed prior to prescribing a SSRI?
- for SNRIs need to check BP before and during treatment.
Which age group is most at risk when prescribed a SSRI? Why? Kids and adults under 25 - increased risk of suicide
Which SSRI has the least CYP interactions - escitalopram (Lexapro).
Good for forgetful people -
fluoxetine (has 2-3 day half life). Also sertraline (27-36 hour ½ life).
Longest acting
fluoxetine has the longest half life 1-2 weeks. When adding or switching antidepressants use caution for 5 weeks [Show Less]