Bupropion side effects

Trazodone, 25 to 100 mg, is often used for insomnia induced by selective serotonin reuptake inhibitors or bupropion. Side effects include serotonin syndrome (when used with other serotonergic drugs), oversedation, a-adrenergic blockade, dizziness, and rarely priapism. 

Side effects. The primary side effects reported with bupropion administration in cigarette smokers are headache, dry mouth, nausea and vomiting, insomnia, and activation. Although most of these adverse effects occur during the first week of treatment, insomnia can persist. Seizures are of exceedingly low occurrence (<0.5%) at doses of 300 mg daily or less, but a prior history of seizures or a seizure disorder contraindicate its use. 

Nortriptyline. Nortriptyhne, a tricychc antidepressant, has been shown in double-blind, placebo-controlled randomized trials to be superior to placebo for smoking cessation (Prochazka et al. 1998). Nortriptyline appears to have efficacy comparable to that of bupropion for smoking cessation (Hall et al. 2002). The efficacy of this agent may be improved with more intensive behavioral therapies (Hall et al. 1998). Nortriptyline s mechanism of action is thought to relate to its noradrenergic and serotonergic reuptake blockade, because these two neurotransmitters have been implicated in the neurobiology of nicotine dependence. Side effects of nortiptyline are typical of tricyclic antidepressants and include dry mouth, blurred vision, constipation, and orthostatic hypotension. Nortriptyline appears to have some utility for smokers with a past history of major depression, and it can be recommended as a second-... 

The occurrence of seizures with bupropion is dose related and may be increased by predisposing factors (e.g., history of head trauma or CNS tumor). At the ceiling dose (450 mg/day), the incidence of seizures is 0.4%. Other side effects include nausea, vomiting, tremor, insomnia, dry mouth, and skin reactions. It is contraindicated in patients with bulimia or anorexia nervosa. 

Bupropion and venlafaxine may also be chosen because of their milder anticholinergic and less frequent cardiovascular side effects. 

Tricyclic drugs have, as the name implies, a three-ring structure, and interfere with reuptake of norepinephrine and/or serotonin into axon terminals. Tricyclic drugs include imipramine (Tofranil), amitriptyline (Elavil), clomipramine (Anafranil), and nortriptyline (Pamelor, Aventil). Tricyclics have the occasional but unfortunate cardiovascular side effects of arrhythmia and postural hypotension. Newer, nontricyclic antidepressants have been developed that are collectively referred to as SSRIs. These have a potent and selective action on serotonin, and lack the cardiovascular side effects of the tricyclics. These include fluoxetine (Prozac), paroxetine (Paxil), sertraline (Zoloft), and fluvoxamine (Luvox). A fifth SSRI, citalopram (Celexa) has been used in Europe and has recently been approved in the United States. Venlafaxine (Effexor) blocks reuptake of norepinephrine and serotonin, while bupropion (Wellbutrin) acts on both dopamine and norepinephrine. 

The most common side effects of bupropion are decreased appetite and abdominal discomfort. But more serious is the risk of seizure when high doses are taken. For this reason, patients with epilepsy should not take bupropion. 

Side effects of bupropion such as stomach upset are relatively mild. The immediate-release form of bupropion increases the risk of seizure in patients... 

Nortriptyline (Pamelor). A recent study suggested that the tricyclic antidepressant nortriptyline, like bupropion, is effective in the treatment of smoking cessation. Nortriptyline does not have any significant effect on dopamine reuptake activity, but it does increase norepinephrine availability. Like bupropion, nortriptyline may therefore reduce the physical symptoms of nicotine withdrawal. Because nortriptyline carries the danger of lethality in overdose and has the unfavorable side effect profile of the tricyclics, we do not recommend its use for smoking cessation. However, it does raise the question as to whether other newer antidepressants that increase norepinephrine activity (e.g., venlafaxine, mirtazapine, duloxetine) may also prove to be effective treatments for nicotine withdrawal. 

Antidepressants. Depression after TBl is routinely treated with antidepressant medicines. Although all antidepressants are potentially helpful, antidepressants prone to burdensome side effects, particularly sedative and anticholinergic side effects, should generally be avoided, as they are likely to be tolerated poorly by these patients. In addition, antidepressants that may increase the risk for seizure, such as many of the older tricyclic antidepressants (TCAs) and bupropion (Well-butrin), should be avoided because post-TBl patients as a rule are already more vulnerable to seizures. 

In cases where the antidepressant response has not been resounding, we prefer switching antidepressants to avoid sexual side effects. The options include bupropion, nefazodone, and mirtazapine, which all effectively treat depression but produce minimal effects on sexual function. Sometimes, if a patient has responded well to one antidepressant but experiences a side effect such as sexual dysfunction, switching within the same class can be a useful approach. 

Q58 Patients receiving bupropion should avoid using promethazine. Bupropion causes sedation as a side-effect. 

Bupropion should not be administered with sedating antihistamines because of the increased risk of seizures. Bupropion is used for smoking cessation therapy and may cause insomnia as a side-effect. Patients are advised to avoid taking bupropion dose at bedtime. 

Drugs that may increase the effects or side effects of bupropion include levodopa, MAOIs, ritonavir, antidepressants, antipsychotics, beta blockers, type 1C antiarrhythmics. 

Geriatric Considerations - Summary Bupropion has several advantages as an antidepressant agent for use in older adults. It has neither the anticholinergic or cardiac toxicities of the tricyclic antidepressants, and has fewer sexual side effects than selective serotonin reuptake inhibitors. Because this drug may lower seizure threshold, it should be used with caution in older adults with increased risk of seizures (e.g., previous stroke, early-onset Alzheimer s disease). 

One of the more worrisome adverse effects of bupropion is seizures. At dosages of 450 mg/day or less, the rate of seizures is 0.4% for individuals without risk factors (Davidson, 1989). Because of this risk, a single dose of bupropion should not exceed 150 mg and a second dose should be separated in time by a minimum of 8 hours. Also, patients who are metabolically unstable (i.e., have bulimia) should be carefully assessed for the risk of seizures before initiating medication. Finally, bupropion is not associated with sexual side effects. 

Newer antidepressants (such as the SSRIs, bupropion, and venlafaxine] probably achieved their impressive popularity primarily because their side-effect profiles were more favorable. Because dry mouth, blurry vision, tachycardia, lethargy, constipation, urinary hesitancy, and arrhythmias are deeply distressing to many, paucity of anticholinergic side effects from SSRIs was especially noteworthy. Convenience and simplicity of use are also favorable qualities for some newer agents. However, the decreased libido, anorgasmia, and erectile problems caused by SSRIs are of note and should be taken into consideration for long-term therapy. 

Several medications have been suggested as antidotes for the sexual side effects associated with antidepressant therapy. Bupropion, 75 or 150 mg/day, has been added to an SSRI regimen with some success in terms of improving libido (Labbate and Pollack 1994). Sildenafil has been used on an as-needed basis before sexual activity (Fava et al. 1998). 

Overall, bupropion has a favorable side-effect profile. The drug is associated with little or no weight gain, has few effects on cardiac conduction, and has minimal sexual side effects. Disadvantages include an increased risk of medication-induced seizures at higher-than-recommended doses. 

Tremor and akathisia also may occur. Management is the same as that for SSRI side effects. Bupropion is not associated with anticholinergic side effects, orthostatic hypotension, weight gain, or cardiac conduction changes. 

Although the efficacy of tricyclic antidepressants in the treatment of unipolar depression is beyond reproach, the side-effect profile of these agents makes them less desirable as first-line therapeutic agents. Introduction of selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine, paroxetine, sertraline, citalopram and fluvoxamine in the past decade has revolutionized the treatment of depression universally. The side-effect profile of SSRIs, such as nausea, diarrhea and sexual dysfunction, is considerably more benign than that of tricyclic drugs. Multiple controlled trials have proven the efficacy of SSRIs vs. placebo (Nemeroff, 1994). Recently, a number of SNRIs (serotonin and noradrenaline reuptake inhibitors) and so-called atypical antidepressants have been marketed that may have additional advantages over SSRIs, such as more rapid onset of action (venlafaxine. mirtazapine) and low sexual side-effect potential ( bupropion, nefazodone). Additionally, it appears that venlafaxine may be more efficacious in cases of treatment-refractory depression (Clerc et al., 1994 Fatemi et al., 1999). Finally, in a recent report (Thase et al., 2001),... 

Bupropion, the only marketed aminoketone antidepressant, also has a side-effect profile different from the other classes of antidepressants. It is essentially devoid of anticholinergic, antihistaminic, and orthostatic hypotensive effects. Its principal adverse effects are consistent with its indirect agonism of dopamine and NE via uptake inhibition and include the following ... 

SSRIs reduce dopamine cell firing in the substantia nigra through their effects on serotonin input to this nucleus. The net result is that they can cause generally mild extrapyramidal side effects (EPS) (500). The most common are restlessness and tremors. The same mechanism is probably responsible for their interaction with other agents that affect central motor systems. Thus, the SSRIs can potentiate the tremor seen with lithium, as well as EPS caused by antipsychotics, bupropion, and psychostimulants (376, 500). 

A number of antidepressants do not fit neatly into the other classes. Among these are bupropion,mirtazapine, amoxapine, and maprotiline (Figure 30-5). Bupropion has a unicyclic aminoketone structure. Its unique structure results in a different side-effect profile than most antidepressants (described below). Bupropion somewhat resembles amphetamine in chemical structure and like the stimulant, has central nervous system (CNS) activating properties. 

Mirtazapine was introduced in 1994 and, like bupropion, is one of the few antidepressants not commonly associated with sexual side effects. It has a tetracyclic chemical structure and belongs to the piperazino-azepine group of compounds. 

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