Venlafaxine monoamine oxidase inhibitors

Although many patients believe that dietary supplements will not interact with medications, recent literature suggests otherwise. Recently, many St. John s wort-drug interactions have been reported in the literature. Cases of patients developing symptoms of serotonin syndrome have been reported with St. John s wort alone and in concomitant therapy with other antidepressants such as monoamine oxidase inhibitors, serotonin reuptake inhibitors, and venlafaxine. St. John s wort may exacerbate the sedative effects of benzodiazepines, alcohol, narcotics, and other sedatives. St. John s wort may decrease the levels of protease inhibitors, cyclosporine, digoxin, and theophylline. 

Monoamine oxidase inhibitors Paroxetine Protriptyline Sertraline Venlafaxine Stimulants Atomoxetine Dextroamphetamine Methylphenidate Modaflnil Pemoline... 

The so-called atypical antidepressants such as venlafaxine and bupropion can be tried, but their safety and efficacy in treating patients with dementia have not been well studied. The older tricyclic antidepressants and monoamine oxidase inhibitors are not tolerated well by demented patients and should be avoided. Two possible exceptions are nortriptyline (Pamelor) and desipramine (Norpramin), but even these should be tried only after the newer antidepressants have proved ineffective. 

Lorazepam is a short-acting benzodiazepine indicated for use in relieving anxiety and insomnia. Lorazepam may also be administered perioperatively to alleviate pain and in status epilepticus. Imipramine is a tricyclic antidepressant, paroxetine is a selective serotonin re-uptake inhibitor, venlafaxine is a serotonin and adrenaline re-uptake inhibitor and moclobemide is a reversible monoamine oxidase inhibitor. Imipramine, paroxetine, venlafaxine and moclobemide are all classified as antidepressants. 

Switching patients to or from a monoamine oxidase inhibitor (MAOl) At least 14 days should elapse between discontinuation of an MAOl and initiation of therapy with venlafaxine. In addition, allow at least 7 days after stopping venlafaxine before starting an MAOl. 

Side effects, mainly due to serotonin reuptake inhibition include G1 upset, nervousness, and sexual dysfunction. SSRls are associated with an increased risk of falls. Hyponatraemia due to SIADH is an uncommon, but important side effect in elderly patients. Selective serotonin and norepinephrine reuptake inhibitors (S SNRls) such as venlafaxine and duloxetine are also useful in older patients. Other heterocyclic antidepressants of importance in older patients because of relative safety include bupro-prion and mirtazepine. They are reserved for patients with resistance to or intolerance of SSRls. Currently, trazodone is used mostly for sleep disturbance in depression in doses of 50-100 mg at bedtime. The monoamine oxidase inhibitors phenelzine. 

Most child and adolescent studies published thus far have focused on the effects of the tricyclic antidepressants (TCAs) and, more recently, the SSRIs. A few open studies have also shown that monoamine oxidase inhibitors (MAOIs) can be used safely with children and adolescents (Ryan et ah, 1988b), but noncompliance with dietary requirements may present a significant problem for minors. Other antidepressants, including the heterocyclics (HTC) (e.g., amoxapine, maprotiline), buproprion, venlafaxine, and nefazodone, have been found to be efficacious for the treatment of depressed adults (APA, 2000), but they have not been well studied for the treatment of MDD in children and adolescents. Therefore, this chapter mainly describes the use of SSRIs and TCAs for youth with MDD. 

Other alternatives to the stimulants that have been studied for treatment of ADHD in children and adults include the tricyclic antidepressants desipramine and nortriptyline the newer antidepressants bupropion, venlafaxine, and atomoxetine the beta-blocker pindolol and the selective monoamine oxidase inhibitor, deprenyl. Across these agents, the number of controlled studies varies from none (nortriptyline) to four (bupropion). Only deprenyl and desipramine have been studied in children with ADHD and tic disorders. 

In contrast, a less extensive but still convincing database has identified important clinical differences in efficacy for antidepressants used to treat patients with atypical or comorbid depression. Individuals with atypical depression (distinct quality of mood, hyperphagia, hypersomnia, psychomotor retardation, rejection sensitivity, and such unusual atypical features as chocolate craving] have superior responses to monoamine oxidase inhibitors (MAOIs], selective serotonin reuptake inhibitors (SSRIs), and perhaps venlafaxine, and most do not respond well to tricyclic antidepressants (TCAs] (Davidson et al. 1982 Liebowitz et al. 1988 Quitkin et al. 1988, 1991). Despite these data, TCAs unfortunately have been the first choice for most atypical patients until SSRIs were introduced. 

Newer antidepressants (eg, fluoxetine, paroxetine, citalopram, venlafaxine) are mostly SSRIs and are generally safer than the tricyclic antidepressants and monoamine oxidase inhibitors, although they can cause seizures. Bupropion (not an SSRI) has caused seizures even in therapeutic doses. Some antidepressants have been associated with QT prolongation and torsade de pointes arrhythmia. SSRIs may interact with each other or especially with monoamine oxidase inhibitors to cause the serotonin syndrome, characterized by agitation, muscle hyperactivity, and hyperthermia (see Chapter 16). 

FIGURE 9-6. Various treatments can be given in combination for panic disorder (i.e., panic combos). The basis of all many combination treatments is a serotonin selective reuptake inhibitor (SSRI). Other antidepressants such as venlafaxine, nefazodone, mirtazapine, tricyclic antidepressants, and monoamine oxidase inhibitors can all have antipanic actions, although they are second-line treatments, as are the benzodiazepines. On the other hand, benzodiazepines are often added to SSRIs, particularly at the initiation of an SSRI and intermittently when there is breakthrough panic. Cognitive and behavioral psychotherapies can also be added to any of these drug treatments. 

In the 1980s an entirely new class of antidepressant arrived with the SSRIs, firstly fluvoxamine immediately followed by fluoxetine (Prozac). Within 10 years, the SSRI class accounted for half of antidepressant prescriptions in the United Kingdom. Further developments in the evolution of the antidepressants have been novel compounds such as venlafaxine, reboxetine, nefazodone and mirtazapine, and a reversible monoamine oxidase inhibitor, moclobemide. 

Antidepressant drugs A major class of psychotropic drugs with diverse chemical configurations including the monoamine oxidase inhibitors (MAOIs), the heterocyclic drugs (composed of mono-, di-, tri-, and hetero-cyclics), the serotonin reuptake inhibitors (fluoxetine, paroxetine, sertraline, trazodone, and venlafaxine), and bupropion are more recent innovations. Antidepressants usually must be taken for several weeks to have the desired effect and they often have a low therapeutic index, so they must be closely monitored. 

The treatment of MDD corresponds to three stages acute phase, continuation phase, and maintenance phase. The gross treatment options should follow the strategies listed in Scheme 9.3. The following are only suggestions, which are based mainly on specific data from accumulated research. The selective serotonin reuptake inhibitors (SSRIs) and venlafaxine are usually considered as first-line treatments. Amitriptyline and clomipramine are second-line treatments. Other tricyclic antidepressants (TCAs) and the monoamine oxidase inhibitors (MAOIs) are third-line treatments. 

Gitlin MJ. Venlafaxine, monoamine oxidase inhibitors, and tiie serotonin syndrome. J CUn Psychopharmacol (1997) 17,66-67. 

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... 

Because of its serotonin-potentiating effect, venlafaxine can cause a serotonin syndrome when combined with monoamine oxidase (MAO) inhibitors (SEDA-20, 9) (SEDA-21,13). 

Many noncyclic antidepressants are now available, including trazodone (Desyrel l), nefazodone (Serzone ), fluoxetine (Prozac ), sertraline (Zolotf ), citalopram (Celexa ), escitalopram (Lexapro ), paroxetine (Paxil ), tluvoxamine (Luvox ), venlafaxine (Effexor ), and bupropion (Wellbutrin ). Bupropion is also marketed under the brand name Zyban tor smoking cessation. Mirtazapine (Remeron ), a tetracyclic antidepressant, has recently become available. In general, these drugs are much less toxic than the tricyclic antidepressants (see p 90) and the monoamine oxidase (MAO) inhibitors (p 269), although serious effects such as seizures and hypotension occasionally occur. Noncyclic and tricyclic antidepressants are described in Table 11-7. 

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