title: Dalfampridine in patients with downbeat nystagmus--an observational study.
abstract: We investigated the effects of dalfampridine, the sustained-release form of 4-aminopyridine, on slow phase velocity (SPV) and visual acuity (VA) in patients with downbeat nystagmus (DBN) and the side effects of the drug. In this proof-of-principle observational study, ten patients received dalfampridine 10 mg bid for 2 weeks. Recordings were conducted at baseline, 180 min after first administration, after 2 weeks of treatment and after 4 weeks of wash-out. Mean SPV decreased from a baseline of 2.12 deg/s ± 1.72 (mean ± SD) to 0.51 deg/s ± 1.00 180 min after first administration of dalfampridine 10 mg and to 0.89 deg/s ± 0.75 after 2 weeks of treatment with dalfampridine (p < 0.05; post hoc both: p < 0.05). After a wash-out period of 1 week, mean SPV increased to 2.30 deg/s ± 1.6 (p < 0.05; post hoc both: p < 0.05). The VA significantly improved during treatment with dalfampridine. Also, 50 % of patients did not report any side effects. The most common reported side effects were abdominal discomfort and dizziness. Dalfampridine is an effective treatment for DBN in terms of SPV. It was well-tolerated in all patients.
authors.affiliation: Department of Neurology and German Center for Vertigo and Balance Disorders (IFBLMU), University of Munich Hospital, Munich, Germany. jens.claassen@googlemail.com
authors.forename: Jens
authors.initials: J
authors.lastname: Claassen
authors.forename: Katharina
authors.initials: K
authors.lastname: Feil
authors.forename: Stanislav
authors.initials: S
authors.lastname: Bardins
authors.forename: Julian
authors.initials: J
authors.lastname: Teufel
authors.forename: Rainer
authors.initials: R
authors.lastname: Spiegel
authors.forename: Roger
authors.initials: R
authors.lastname: Kalla
authors.forename: Erich
authors.initials: E
authors.lastname: Schneider
authors.forename: Klaus
authors.initials: K
authors.lastname: Jahn
authors.forename: Roman
authors.initials: R
authors.lastname: Schniepp
authors.forename: Michael
authors.initials: M
authors.lastname: Strupp
mesh_terms: D015761:4-Aminopyridine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000473:pathology; D003692:Delayed-Action Preparations; D005133:Eye Movements / Q000502:physiology; D005260:Female; D005403:Fixation, Ocular / Q000502:physiology; D020233:Gait Disorders, Neurologic / Q000209:etiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination; D009759:Nystagmus, Pathologic / Q000188:drug therapy* / Q000209:etiology; D010865:Pilot Projects; D011115:Polyneuropathies / Q000209:etiology; D026902:Potassium Channel Blockers / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D014787:Vision Tests; D014792:Visual Acuity / Q000502:physiology
chemical_list: D003692:Delayed-Action Preparations; D026902:Potassium Channel Blockers; D015761:4-Aminopyridine