ABSTRACT
BACKGROUND: Amantadine hydrochloride and rimantadine hydrochloride are recommended by the Centers for Disease Control and Prevention for prophylaxis of influenza A. While data suggest that rimantadine is better tolerated, there are no data examining the rate of adverse reactions in elderly patients who receive amantadine vs rimantadine. Our objective was to assess the adverse reaction rate in elderly nursing home patients receiving sequential amantadine and rimantadine for influenza A prophylaxis. METHODS: Data were collected in 156 nursing home patients (70% women; mean+/-SD age, 83.7+/-10.1 years) in a single care setting who received sequential therapy with amantadine and rimantadine during the 1997-1998 influenza season. Patients were assessed for central nervous system adverse effects and therapy discontinuation occurring with each agent. RESULTS: Twenty-nine (18.6%) of the 156 patients experienced an adverse effect when receiving amantadine compared with 3 patients (1.9%) when rimantadine was given (P<.01). Drug use was discontinued due to adverse events in 17.3% (n = 27) of the amantadine courses and 1.9% (n=3) of the rimantadine courses (P<.001). Confusion was the most frequently observed adverse event (amantadine, 10.6%; rimantadine, 0.6%; P<.001). Multivariate logistic regression analysis showed that significant risk factors for central nervous system adverse events included male sex (odds ratio, 3.65), reduced calculated creatinine clearance (odds ratio, 1.78), and use of amantadine (odds ratio, 12.73). CONCLUSIONS: Amantadine use was associated with a significantly higher incidence of central nervous system adverse events than rimantadine use in this elderly population receiving influenza prophylaxis. In addition, the discontinuation rate of amantadine was significantly higher than that with rimantadine.
Subject(s)
Amantadine/adverse effects , Antiviral Agents/adverse effects , Central Nervous System Diseases/chemically induced , Influenza A virus/drug effects , Influenza, Human/prevention & control , Rimantadine/adverse effects , Adverse Drug Reaction Reporting Systems , Aged , Aged, 80 and over , Amantadine/administration & dosage , Antiviral Agents/administration & dosage , Central Nervous System Diseases/diagnosis , Female , Homes for the Aged , Humans , Influenza, Human/transmission , Male , Neurologic Examination/drug effects , Nursing Homes , Rimantadine/administration & dosage , Risk FactorsABSTRACT
In rodents and other mammals, prenatal stress disrupts both sexual differentiation and sexual behavior. The present study examined the area of the anterior division of the anterior commissure (the Aca) in coronal, thionin-stained sections of prenatally stressed (P-S), and control male and female rats. Pregnant rats were exposed to thrice-daily heat, light, and restraint stress or left undisturbed during days 15-22 of pregnancy. Adult P-S and control males and females were killed, perfused, and their brains removed. Serial coronal sections (total of approximately 200 microm) through the rostral portion of the Aca (the rAca) were taken and stained with thionin. The sections were examined and traced under x25 using computerized microscopy to obtain the area in mm2. The data revealed that control females had a larger rAca compared to control males, and that P-S males had a larger rAca compared to control males; further, control males and P-S females were not significantly different, nor were control females and P-S males. These results suggest that, in rats, the Ac may be sexually dimorphic (in a direction similar to that described in humans) and that prenatal stress an event that modifies sex-typical behavior, physiology, and neuroanatomy reverses that sex difference.
