Venlafaxine MAOIs

The effects of buspirone are decreased when the drug is administered with fluoxetine Increased serum levels of buspirone occur if the drug is taken with erythromycin or itraconazole Should any of these combinations be required, the dosage of buspirone is decreased to 2.5 mg BID, and the patient is monitored closely. Venlafaxine blood levels increase with a risk of toxicity when administered witii MAOIs or cimetidine There is an increased risk of toxicity when trazodone is administered with the phenothiazines and decreased effectiveness of trazodone when it is administered with carbamazepine Increased serum digoxin levels have occurred when digoxin is administered with trazodone There is a risk for increased phenytoin levels when phenytoin is administered witii trazodone... 

The SSRIs are first-line pharmacotherapy for PTSD. Venlafaxine, the TCAs, and MAOIs may also be effective, but they have less favorable side-effect profiles. 

Amitriptyline and imipramine, and the MAOI phenelzine, can be considered second- or third-line drugs for PTSD after SSRIs have failed. Mirtaza-pine and venlafaxine may also be effective. 

Venlafaxine MAOIs Potential for hypertensive crisis, serotonin syndrome, delirium... 

Many commonly used medications also contain substances that are eliminated by the MAOIs and must not be taken by these patients. The list of medications to be avoided inclndes the narcotic pain reliever meperidine (Demerol), and many over-the-connter cold remedies containing dextromethorphan or pseudoephedrine. Finally, patients taking MAOIs must also avoid medications that elevate serotonin levels. This inclndes certain appetite snppressants and antidepressants including the SSRIs, venlafaxine, duloxetine, mirtazapine, nefazodone, and trazodone. Medications that interact with the MAOIs cannot be taken until at least 2 weeks after the MAOI has been stopped. 

Newer Generation Antidepressants. All SSRIs have been shown effective in the treatment of panic disorder. Of these, flnoxetine (Prozac), paroxetine (Paxil), and sertraline (Zoloft), as well as the SNRI venlafaxine ER (Effexor XR), have received FDA approval for the treatment of panic disorder. Because they are safer and easier to tolerate, SSRls/SNRls have largely supplanted the MAOIs and TCAs as standard treatments (along with benzodiazepines) for panic disorder. 

Serotonin-Boosting Antidepressants. The SSRIs have also been studied in the treatment of generalized social anxiety disorder, and paroxetine, sertraline, and venlafaxine are effective. Preliminary data suggests that the serotonin-boosting atypical antidepressants (mirtazapine and nefazodone) may also be helpful. Like the MAOIs, they appear to be effective at doses comparable to those used to treat depression. They may help avoidant patients to gradually increase their social interaction and become more assertive. 

Serotonin-boosting antidepressants or longer-acting benzodiazepines are also both suitable first-line treatments for APD. For APD patients who are also troubled by depression, an antidepressant is obviously preferable. We also prefer to use antidepressants rather than benzodiazepines to treat APD patients who have a history of substance abuse. The current data suggests that any of the SSRls as well as nefazodone, mirtazapine, and venlafaxine may be helpful. When these do not work, a MAOI is a reasonable alternative provided the patient is willing to commit to the dietary regimen. 

Drugs that may affect trazodone include carbamazepine, phenothiazines, and venlafaxine. Drugs that may be affected by trazodone include alcohol, barbiturates, CNS depressants, digoxin, MAOIs, phenytoin, and warfarin. 

Hypersensitivity to venlafaxine or any ingredients of the product concomitant use in patients taking MAOIs. 

MAOIs Because venlafaxine is an inhibitor of norepinephrine and serotonin reuptake, it is recommended that venlafaxine not be used in combination with an MAOl or within 14 days of discontinuing treatment with an MAOI. Allow at least 7 days after stopping venlafaxine before starting an MAOI. 

Drugs that may affect venlafaxine include cimetidine, cyproheptadine, and MAOIs. Drugs that may be affected by venlafaxine include clozapine, desipramine, haloperidol, indinavir, St. John s wort, trazodone, sibutramine, sumatriptan, and warfarin. 

Antidepressants MAOIs, TCAs, SSRIs, SNRIs, mirtazapine, venlafaxine Amphetamines, phentermine, methylphenidate, sibutramine... 

C. Nortriptyline (Pamelor) is a TCA, and as a class these drugs require at least one steady-state blood level to safely and effectively use the medication. Paroxetine, venlafaxine, and bupropion have not had blood levels correlated to response, and their relatively low toxicity does not require therapeutic blood monitoring. Nardil is a MAOI, which can be... 

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. 

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. 

Venlafaxine does not appear to inhibit cytochrome P450 enzymes significantly, and it is the antidepressant least likely to contribute to protein-binding interactions. Because of the risk of serotonin syndrome, venlafaxine should not be combined with MAOIs. 

Social phobia SSRIs, MAOIs, benzodiazepines, buspirone, venlafaxine... 

Venlafaxine shares similar advantages with the SSRIs over the TCAs and the MAOIs. In addition, potential advantages of venlafaxine over the SSRIs are as follows ... 

Although more stimulating antidepressants (e.g., bupropion, SSRIs, venlafaxine, or certain MAOIs) do not potentiate alcohol, they can produce insomnia. To minimize this problem, the dose may be given earlier in the day. TCAs may cause episodes of excitement (rare), confusion, or mania, usually in patients with an underlying psychotic illness, suggesting that a preexisting disorder must be present for these drugs to exert any psychotomimetic effects. 

There is a great disparity of current knowledge regarding the effects of antidepressants on GYP enzymes. There have been almost no studies to test the potential effects of TCAs, MAOIs, and trazodone on GYP enzymes. There has only been one study with bupropion but it demonstrated that bupropion produces substantial inhibition of GYP 2D6 comparable with the effect of fluoxetine and paroxetine. In contrast to studies in these antidepressants, there have been extensive in vitro and in vivo studies of SSRIs, nefazodone, and venlafaxine. 

MAOIs have the most serious pharmacodynamic interactions of any antidepressant class. As discussed earlier, they can cause a hypertensive crisis and the serotonin syndrome. They potentiate the hypertensive effects of most sympathomimetic amines, as well as tyramine, which is the reason for the avoidance of over-the-counter preparations containing such agents, in addition to the tyramine-free diet ( 508, 509). The serotonin syndrome occurs most often when MAOIs are used in combination with SSRIs and venlafaxine but it can also occur when MAOIs are used with tryptophan, 5-hydroxytryptophan, and some narcotic analgesics. In addition, MAOIs can also significantly potentiate the sedative and respiratory depressant effects of narcotic analgesics. 

MAOIs, TCAs, lithium, clomipramine (alone or with topical steroids), fluoxetine, and fluvoxamine may reduce the frequency and intensity of this disorder ( 210, 226, 255, 256, 257, 258, 259, 260 and 261) however, controlled trials are needed to conclusively establish efficacy. Relapse after initial improvement has also been reported, however. Data also indicate that both trichotillomania and OCD may respond to venlafaxine ( 262, 263). For children, such treatments should be reserved for only those with the more severe, refractory forms. 

The SNRIs have relatively fewer CYP450 interactions than the SSRIs. Venlafaxine is a substrate but not an inhibitor of CYP2D6 or other isoenzymes, whereas desvenlafaxine is a minor substrate for CYP3A4. Duloxetine is a moderate inhibitor of CYP2D6 and so may elevate TCA and other CYP2D6 substrate levels. Like all serotonergic antidepressants, SNRIs are contraindicated in combination with MAOIs. 

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