Fluvoxamine drug withdrawal

Gastrointestinal adverse effects are one of the major disadvantages of SSRIs. The most common is nausea, and the incidence is said to be 20% or more for paroxetine (45,46), sertraline (47), fluvoxamine (5), fluoxetine (48), and citalopram (10,49). Although nausea can lead to drug withdrawal, it usually disappears after a few weeks. Other gastrointestinal symptoms that occur commonly with fluoxetine and sertraline are loose stools and diarrhea (47,48,50), while constipation has been more often reported with fluvoxamine (5) and paroxetine (45,46). 

Sexual function SSRIs can cause sexual dysfunction, particularly reduced libido, impaired orgasm in women, and inhibition of ejaculation or erectile difficulties in men. There have been two reports of unusual male sexual dysfunction. In two cases of spermatorrhea (excessive emission of semen without orgasm or erection) in men taking fluvoxamine, the problem resolved on drug withdrawal [IS ]. Spontaneous ejaculations occurred daily in a 27-year-old man after he had taken citalopram for 2 weeks [16 ]. They were unrelated to sexual fantasies, arousal, erection, or any sensation of orgasm and resolved on drug withdrawal. They did not recur when he took paroxetine. 

A higher percentage of patients would be expected to relapse in the crossover design for two reasons. First, a significant portion of the patients in the crossover study had, in fact, responded specifically to the drug treatment. After a period of stabilization, these patients were randomly reassigned to placebo and thus would be expected to relapse. Second, a basic problem in the crossover design is that withdrawal symptoms can mimic the recurrence of depressive symptoms. That is true for the SSRIs, particularly fluvoxamine and paroxetine, because of their relatively short half-lives. 

A study in 11 healthy subjects found that paroxetine 20 mg daily for 16 days had no effect on the response to a 6-mg dose of subcutaneous sumatriptan, as measured by prolactin levels. The sumatriptan levels remained unaltered, its cardiovascular effects were unchanged and no clinically significant adverse effects occurred. Other studies report that the concurrent use of sumatriptan and SSRIs (fluoxetine 20 to 60 mg daily, fluvoxamine 200 mg daily, paroxetine 20 to 50 mg daily, sertraline 50 to 100 mg daily) was successful and uneventful. No adverse effects have been noted in 148 other patients. However, a case report describes a 65-year-old woman who had been taking paroxetine 20 mg [daily] for a number of years, who developed confusion, strange behaviour, sinus tachycardia, hypertension and hyperthermia shortly after starting sumatriptan. The serotonin syndrome was diagnosed, and she recovered completely on withdrawal of the two drugs. ... 

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