Topiramate leukopenia on clozapine

with clozapine 550 mg a day, along with lithium at therapeutic levels, in a residential facility. He met DSM-IV criteria for Bipolar I, Manic Disorder. The latter had been chronic and severe. Starting at age 16, he was sleepless. He had rapid pressured speech that became hard to follow after 2 minutes due to his flight of ideas. He was expelled from three expensive private schools in Europe. While more stable on clozapine, he still designed, made, and exhibited jewelry, composed and recorded songs, wrote a book on psychiatry, took a course in photography, and painted, all simultaneously. He had not used marijuana for 5 years. The mania was unremitting for 7 years.He had been hospitalized a dozen times,and failed to respond to multiple antipsychotics and mood stabilizers. He assaulted staff and family many times. He never committed profit-making crimes. On clozapine, he became quieter, only hypomanic, but no longer dangerous to self or others. However, his mother objected to his 25 kg weight gain.Because he had been so treatment-resistant prior to the use of clozapine, tapering the drug was unwise. Topiramate, as a mood stabilizer, and as an increasingly used weight suppressor,was proposed.His white blood cell count (WBC) had ranged from 9000/μL to 10,000/μL for 2 years on clozapine. Topiramate was added, 25 mg BID for 1 week, 50 mg BID for 1 week, then 100 mg BID for 1 week, and finally, 200 mg BID. Complete blood counts continued every 2 weeks, per the standard clozapine protocol. They were normal for 4 weeks. After 1 week of topiramate 200 mg BID, his WBC was European Child & Adolescent Psychiatry (2004) 13:51–52 DOI 10.1007/s00787-004-0323-0 LETTER TO THE EDITORS