Adverse effects of amantadine and oseltamivir used during respiratory outbreaks in a center for developmentally disabled adults.
OBJECTIVE
Antiviral prophylaxis is recommended for the control of institutional influenza A outbreaks. In long-term-care institutions other than nursing homes, neither the seriousness of influenza nor the risks and benefits of antiviral prophylaxis is clearly understood. We studied the severity of illness due to influenza among adults residing in a center for the developmentally disabled and assessed adverse reactions to amantadine and oseltamivir prophylaxis.


METHODS
Data were collected from the charts of consenting residents. Complications of upper respiratory tract illness were recorded. Potential adverse events were documented during amantadine and oseltamivir therapy, and during a baseline period with neither medication.


RESULTS
The median age of the 287 participants was 46.4 years. Only 15 (5%) were older than 65 years, and 69 (24%) had chronic underlying medical illness placing them at high risk for influenza. Of the 122 residents with an upper respiratory tract infection, 16 (13%) developed pneumonia, 12 (9.8%) were hospitalized, and 5 (4%) died. Twenty-eight (25%) of 112 residents had an adverse neurologic event while receiving amantadine prophylaxis, compared with 3 (2.7%) receiving no antiviral medication and 5 (4.5%) receiving oseltamivir (P < .001). Sixteen percent of the residents discontinued amantadine due to adverse events; in contrast, adverse events were identified in 2.9% of the residents prescribed oseltamivir, and none discontinued therapy.


CONCLUSIONS
Viral respiratory tract infections are associated with a high risk of complications in this population. The rate of adverse neurologic events associated with amantadine was significantly higher than that associated with oseltamivir.
McGeer
Allison J
AJ
Department of Microbiology, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada.
Lee
Wayne
W
Loeb
Mark
M
Simor
Andrew E
AE
McArthur
Margaret
M
Green
Karen
K
Benjamin
Jonathan Hayfron
JH
Gardner
Charles
C
D000081:Acetamides / Q000009:adverse effects*; D000328:Adult; D000368:Aged; D000547:Amantadine / Q000009:adverse effects*; D000998:Antiviral Agents / Q000009:adverse effects*; D002648:Child; D015897:Comorbidity; D002658:Developmental Disabilities / Q000453:epidemiology; D004196:Disease Outbreaks / Q000517:prevention & control* / Q000706:statistics & numerical data; D005260:Female; D005767:Gastrointestinal Diseases / Q000139:chemically induced; D006801:Humans; D015994:Incidence; D017053:Infection Control / Q000379:methods / Q000706:statistics & numerical data; D008134:Long-Term Care / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000139:chemically induced; D009864:Ontario / Q000453:epidemiology; D053139:Oseltamivir; D012141:Respiratory Tract Infections / Q000188:drug therapy* / Q000453:epidemiology*; D012720:Severity of Illness Index
D000081:Acetamides; D000998:Antiviral Agents; D053139:Oseltamivir; D000547:Amantadine