MAOIs Citalopram

Citalopram MAOIs Potential for hypertensive crisis, serotonin syndrome,... 

Citalopram is a selective serotonin re-uptoke inhibitor (SSRI). These tend to have fewer ontimuscarinic effects than tricyclic antidepressant (TCA) drugs, such as dry mouth and constipation however, SSRIs tend to cause gastrointestinal effects, such as nausea and vomiting. MAOIs are monoamine oxidase inhibitors. 

Citalopram (Celexa) [Antidepressant/SSRI] WARNING Closely monitor for worsening depression or emergence of suicidality, particularly in pts <24 y Uses Depression Action SSRI Dose Initial 20 mg/d, may t to 40 mg/d X in elderly hqjatic/renal insuff Caution [C, +/-] Hx of mania, Szs pts at risk for suicide Contra MAOI or w/in 14 d of MAOI use Disp Tabs, cap, soln SE Somnolence, insomnia, anxiety, xerostomia, diaphoresis, sexual dysfxn Notes May cause X Na /SIADH Interactions t Effects W/ azole antifungals, cimetidine, Li, macrolides, EtOH t effects OF BBs, carbamazepine, CNS drugs, warfarin X effects W/ carbamaz ine X effects OF phenytoin may cause fatal Rxn W/ MAOIs EMS Use caution w/ CNS depressants, may need a reduced dose concurrent EtOH... 

The most common interactions with SSRIs are pharmacokinetic interactions. For example, paroxetine and fluoxetine are potent CYP2D6 inhibitors (Table 30-4). Thus, administration with 2D6 substrates such as TCAs can lead to dramatic and sometimes unpredictable elevations in the tricyclic drug concentration. The result may be toxicity from the TCA. Similarly, fluvoxamine, a CYP3A4 inhibitor, may elevate the levels of concurrently administered substrates for this enzyme such as diltiazem and induce bradycardia or hypotension. Other SSRIs, such as citalopram and escitalopram, are relatively free of pharmacokinetic interactions. The most serious interaction with the SSRIs are pharmacodynamic interactions with MAOIs that produce a serotonin syndrome (see below). 

All SSRIs have common 5-HT agonistic effects and because of this, SSRIs have common interactions and side effects. SSRIs are potent inhibitors of serotonin reuptake by CNS neurons and may interact with other drugs such as monoamine oxidase inhibitors (MAOIs) or circumstances which cause serotonin release. A minimum 2 weeks wash-out period should be observed between stopping a MAOI and starting an SSRI. Conversely, a MAOI should not be started for at least 1 week after an SSRI has been stopped, 5 weeks after fluoxetine, and 2 weeks for paroxetine and sertraline. Escitalopram and citalopram are hypersensitive to each other. 

Antidepressants can be crudely divided into three classes the monoamine oxidase inhibitors (MAOIs), the tricylic antidepressants (TCAs) and related compounds, and the selective serotonin reuptake inhibitors (SSRIs). HPLC-ED did not feature in a review of methods for five leading SSRIs citalopram, fluoxetine, fluvoxa-mine, paroxetine and sertraline. More recently, Clement et measured venlafaxine (Figure 6.17) and 0-desmethylvenlafaxine by HPLC with coulometric... 

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