MAOIs Buspirone

Trazodone + SSRIs, buspirone, MAOIs —> serotonin syndrome possible due to additive serotonergic effects. 

Buspirone + MAOIs —> hypertension due to increased serotonergic effect. 

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... 

Buspirone generally is well tolerated and does not cause sedation. Most common side effects include dizziness, nausea, and headaches. Drugs that inhibit CYP3A4 (e.g., verapamil, diltiazem, itraconazole, fluvoxamine, nefa-zodone, and erythromycin) can increase buspirone levels. Likewise, enzyme inducers such as rifampin can reduce buspirone levels significantly. Bupirone may increase blood pressure when coadministered with an monoamine oxidase inhibitor (MAOI). 

Buspirone may increase haloperidol levels and elevate blood pressure in patients taking a monoamine oxidase inhibitor (MAOI). 

Buspirone does not share any of the problematic benzodiazepine properties such as sedation, motor impairment, addiction, physical dependence, or withdrawal. The most common side effects of buspirone include dizziness, nausea, headache, fatigue, and dry mouth. Despite its activity in the serotonin system, buspirone is not associated with the sexual side effects that plague the SSRIs, SNRIs, MAOIs, and TCAs. 

Drugs that affect nefazodone include general anesthetics, sibutramine, sumatriptan, buspirone, carbamazepine, and propranolol. Drugs that may be affected by nefazodone include alcohol, benzodiazepines, buspirone, carbamazepine, cisapride, digoxin, haloperidol, HMG-CoA reductase inhibitors, MAOIs, propranolol, St. John s wort, cyclosporine, and tacrolimus. 

Buspirone (BuSpar) [Anxiolytic] WARNING Closely monitor for worsening depression or emergence of suicidality Uses Short-term relief of anxiety Action Antianxiety antagonizes CNS serotonin receptors Dose Initial 7.5 mg PO bid T by 5 mg q2-3d to effect usual 20-30 mg/d max 60 mg/d Contra w/ MAOI Caution [B, /-] Avoid w/ severe hepatic/renal insuff Disp Tabs SE Drowsiness, dizziness, HA, N, EPS, serotonin synd, hostility, depression Notes No abuse potential or physical/psychologic d endence Interactions T Effects W/ erythromycin, clarithromycin, itraconazole, ketoconazole, diltiazem, verapamil, grapefruit juice effects W/ carbamazepine, rifampin, phenytoin, dexamethasone, phenobarbital, fluoxetine EMS T Sedation w/ concurrent EtOH use grapefruit juice may T risk of adverse effects OD May cause dizziness, miosis, N/V symptomatic and supportive... 

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

Irreversible MAOIs + sympathomimetic amines, tyramine-containing foods ("cheese effect") and buspirone — hypertension, possibly leading to stroke. 

MAOIs BUSPIRONE Cases of hypertension Uncertain Monitor BP closely... 

The antidepressants, generally, produce their therapeutic effects by blocking the reuptake of one or more catecholamines (norepinephrine, serotonin, and dopamine), which leads to a decrease (down-regulation) of the number of post-synaptic receptors—generally within seven to twenty-one days, coinciding with the onset of clinical effect (see chapter 3). The MAOIs block monoamine oxidase, which metabolizes the catecholamines stored at the nerve ending of the presynaptic neuron—thereby making more catecholamine available. Stimulants increase the release of catecholamines. Buspirone is a 5-HT lA receptor blocker. 

Buspirone (BuSpar)—contraindicated with MAOIs Seriously elevated blood pressure (hypertensive crisis), elevated temperature, seizures, cerebral hemorrhage, death... 

Buspirone is a well-tolerated drug, the most commonly reported side effects being transient dizziness, light-headedness, headache, and gastrointestinal disturbances. Other limitations of buspirone are its delayed onset of action (fewday s to a few weeks) and a significant drug interaction with MAOIs. 

The metabolic profile of anxiolytic agents has important ramifications for their clinical use. This section discusses the metabolism of the benzodiazepinesand buspirone in some detail. The metabolism of the SSRIs, TCAs, and MAOIs is covered in the chapter on antidepressants. 

Four cases of significant blood pressure elevation, which occurred during the use of buspirone and either phenelzine or tranylcypromine, have been reported to the FDA s Spontaneous Reporting System. One patient was a 75-year-old woman and the other 3 patients were men aged between 30 and 42 years. The report does not say how much the blood pressure rose, or how quickly, and no other details are given. On the basis of this rather sparse information the manufacturers of buspirone " recommend that it should not be used concurrently with an MAOI. 

A small study in healthy subjects found no problems when moclobemide was given 24 hours after clomipramine. However, the serotonin syndrome occurred in 3 patients when clomipramine was replaced by mo-clobemide without a washout period or with only a 24-hour washout period, " and in another patient when moclobemide was replaced by clomipramine after only 12 hours. A fatal case of the serotonin syndrome occurred in a patient taking clomipramine and amitriptyline, with symptoms manifesting within 30 minutes of a 300-mg dose of moclobemide. Two other patients developed fatal serotonin syndrome after taking moderate overdoses of moclobemide and clomipramine. The serotonin syndrome has been reported in at least 8 other cases of moclobemide and clomipramine overdose, one of which also involved tramadol (see also MAOIs + Opioids Tramadol, p.ll41), another fluoxetine (see also MAOIs or RIMAs + SSRIs, p.l 142), and yet another buspirone (see also MAOIs or RIMAs + Buspirone, p.l 133). Conversely, a case of an overdose of moclobemide and clomipramine resulted in no adverse effects except sinus tachycardia. ... 

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