Trazodone serum level

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... 

There are anecdotal reports of trazodone decreasing heparin serum levels by about 20%. Clomipramine, nortriptyline, and trazodone can raise warfarin serum levels up to 30%. 

Phenytoin, a liver enzyme inducer, decreases serum levels of TCAs (especially desipramine and clomipramine). An increase in serum levels of nortriptyline and trazodone has also been reported. In these cases, the net effect of enzyme induction (by phenytoin) and enzyme inhibition (by TCAs) seem to be in favor of the inhibitory effects. Carbamazepine also induces liver enzymes, with a consequent reduction in serum levels of TCAs (amitriptyline, desipramine, doxepin, and nortriptyline). These effects of carbamazepine have not been observed with clomipramine, but have been reported with selective serotonin reuptake inhibitors (SSRIs). 

For MDD with severe anxiety, mirtazapine, TCAs, trazodone, and benzodiazepines should be considered as adjunctive therapy. If the patient is not at least moderately improved after 4-8 weeks, the treatment regimen should be reappraised. Compliance should be checked. It is important to consider pharmacokinetic/pharmacodynamic factors (this may require an evaluation of serum levels of the antidepressant medication), general medical comorbidities, and comorbid psychiatric disorders, including substance abuse and significant psychosocial problems. The initial therapeutic treatment dose should be gradually maximized. For partial responders, the trial should be extended by... 

This seems to be the first and only report of raised carbamazepine levels with trazodone, and its general importance is unknown. The rise was only moderate and in this case was clinically irrelevant, but a carbamazepine serum rise of 26% might possibly be of importance in those patients with serum levels already near the top end of the therapeutie range. 

An elderly man with multi-infarct dementia and behavioural disturbances, taking clozapine, glibenclamide (glyburide), trazodone and melatonin, was hospitalised for agitation on the last day of a 10-day course of ciprofloxacin 500 mg twice daily. When the ciprofloxacin course was completed, his plasma clozapine serum levels fell from 90 nanograms/mL to undetectable levels (lower limit of detection being 50 nanograms/mL). ... 

St. John s wort Mild to moderate depression Gastrointestinal upset, photo-sensitivity. Mild serotonin syndrome with the following medications paroxetine, trazodone, sertraline, and nefazodone. May decrease digoxin levels. May decrease cyclosporine serum concentrations. Combined oral contraceptives—breakthrough bleeding. 

A single case report describes a moderate rise in serum carbamazepine levels in a patient given trazodone. Carbamazepine may moderately decrease trazodone levels. 

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