Successful treatment of chronic fatigue syndrome with duloxetine and trijodthyronine--a case study.

To the Editors: On May 2, 2007, the US Food and Drug Administration expanded black box warnings of all antidepressant medications to include information about an increased risk of suicidality in young adults aged 18 to 24 years. The advisory committee made this decision after evaluating the results of meta-analyses of participants enrolled in 372 randomized antidepressant trials over the past 20 years. A differential risk of antidepressantinduced suicidality among various age groups has previously been reported in the literature. Martinez et al found an increased risk of suicidality with selective serotonin reuptake inhibitors (SSRIs) compared with tricyclic antidepressants in patients 18 years and younger. Another case-control study found that severely depressed patients aged 6 to 18 years treated with antidepressants were at a significantly higher risk of suicide attempts and completed suicides compared with adults. Elderly patients have been found to have nearly 5-fold higher risk of completed suicide during the first month of therapy with SSRIs. The study also reported consistent results when venlafaxine was included in the analyses with SSRIs. Venlafaxine (which inhibits reuptake of 5-hydroxytryptamine [5-HT] and norepinephrine [NE] at higher doses) shares a similar proposed mechanism of action as duloxetine. Duloxetine has been shown to have 100-fold higher affinity for human 5HT transporters and at least 300-fold higher affinity for NE transporters in vitro compared with venlafaxine. It is unknown whether more potent 5-HT and NE blockade correlates with increased suicidal ideation during initial antidepressant treatment. CASE 1 Mr A is a 37-year-old married white man admitted for a major depressive episode after his wife discovered that he bought equipment to poison himself with carbon monoxide. Two months before admission, the patient started treatment with duloxetine for chronic back pain. The dose was later increased to 60 mg/d for additional pain relief. Two weeks before admission, duloxetine was increased again to 90 mg/d. Seven days later, the patient reported having thoughts of suicide and was admitted to the University of Kansas Medical Center psychiatry unit in August 2005. Mr A had no previous psychiatric hospitalization or any outpatient psychiatric care. Before taking duloxetine, Mr A had never taken any psychotropic medications. He did not have prior suicidal attempts or suicidal ideations. No signs of character pathology or poor impulse control were elicited. The patient did have 3 first-degree relatives with an affective disorder but no family history of suicide. Upon admission to inpatient psychiatry, Mr A appeared severely distressed. He continuously repeated the phrase: BMy wife deserves better.[ Apparently, the patient developed a romantic interest with a woman at work. He denied any infidelity but started having guilt about the thoughts. Mr A_s target symptoms also included anxiety, insomnia, and irritability. The patient was unable to state exactly why he wanted to commit suicide. Mr A reported that he did not feel sad and could think of no reason for him to wish to die. He described a loving and supportive marriage. Mr A was steadily employed with no recent additional social stressors. On Day 1 of hospitalization, duloxetine was tapered off, and escitalopram was started. The patient was also started on risperidone 1 mg at bedtime for psychic agitation. Within days of discontinuing duloxetine, Mr A reported decreased anxiety and no thoughts of suicide. After 3 days, he was discharged home on escitalopram and risperidone.