Adverse Drug Reaction Reports Regarding Abnormal Behavior After Oseltamivir Use in Children as Reported by Consumers or Healthcare Professionals

Figures & data

Figure 1 Selection of the analysis set and exclusion criteria.

Abbreviation: ADR, adverse drug reaction.

Figure 2 (A) Total number of spontaneous reports in the JADER. (B) Total number of ADR reports in children aged <20 years.

Table 1 Number of ADR Reports Associated with Oseltamivir by Type of Reporter in Each Time Period

Reporter	ADR	Total April 2004–May 2020		Before the News* April 2004–December 2005		Between the News and the Letter** January 2006–March 2007		After the Letter April 2007–May 2020
		Total, n (%)	n/Quarter	Total, n (%)	n/Quarter	Total, n (%)	n/Quarter	Total, n (%)	n/Quarter
a. <10 years (n=574)
Healthcare professionals only (n=541)	Other than abnormal behavior	177 (32.7)	2.26	48 (8.9)	6.86	32 (5.9)	6.40	97 (17.9)	1.83
	Abnormal behavior	364 (67.3)	5.03	19 (3.5)	2.71	52 (9.6)	10.40	293 (54.2)	5.53
Healthcare professionals and patients (n=12)	Other than abnormal behavior	3 (25.0)	0.05	0 (0.0)	0	0 (0.0)	0	3 (25.0)	0.06
	Abnormal behavior	9 (75.0)	0.14	0 (0.0)	0	3 (25.0)	0.60	6 (50.0)	0.11
Patients only (n=21)	Other than abnormal behavior	4 (19.0)	0.06	0 (0.0)	0	0 (0.0)	0	4 (19.0)	0.08
	Abnormal behavior	17 (81.0)	0.26	0 (0.0)	0	0 (0.0)	0	17 (81.0)	0.32
b. 10–19 years (n=315)
Healthcare professionals only (n=294)	Other than abnormal behavior	84 (28.6)	1.29	15 (5.1)	2.14	24 (8.2)	4.80	45 (15.3)	0.85
	Abnormal behavior	210 (71.4)	3.23	9 (3.1)	1.29	68 (23.1)	13.60	133 (45.2)	2.51
Healthcare professionals and patients (n=7)	Other than abnormal behavior	3 (33.3)	0.05	2 (0.0)	0	1 (16.7)	0.40	1 (16.7)	0.02
	Abnormal behavior	4 (66.7)	0.06	2 (33.3)	0.29	1 (16.7)	0.20	1 (16.7)	0.02
Patients only (n=14)	Other than abnormal behavior	1 (7.1)	0.02	0 (0.0)	0	0 (0.0)	0	1 (7.1)	0.02
	Abnormal behavior	13 (92.9)	0.20	0 (0.0)	0	0 (0.0)	0	13 (92.9)	0.25

Notes: *ADRs, such as abnormal behavior, after the administration of oseltamivir were frequently reported in the news in November 2005. **The Dear Healthcare Professional letter about abnormal behavior after the administration of oseltamivir was published by a Japanese regulatory agency on March 20, 2007.

Abbreviation: ADR, adverse drug reaction.

Table 2 Number of ADR Reports Associated with Zanamivir or Amantadine by Type of Reporter in Each Time Period

Reporter	ADR	Total April 2004–May 2020		Before the News* April 2004–December 2005		Between the News and the Letter** January 2006–March 2007		After the Letter April 2007–May 2020
		Total, n (%)	n/Quarter	Total, n (%)	n/Quarter	Total, n (%)	n/Quarter	Total, n (%)	n/Quarter
a. <10 years (n=211)
Healthcare professionals only (n=172)	Other than abnormal behavior	39 (22.7)	2.26	1 (0.6)	6.86	1 (0.6)	6.40	37 (21.5)	1.83
	Abnormal behavior	133 (77.3)	5.03	4 (2.3)	2.71	5 (2.9)	10.40	124 (72.1)	5.53
Healthcare professionals and patients (n=19)	Other than abnormal behavior	10 (52.6)	0.05	0 (0.0)	0	0 (0.0)	0	10 (52.6)	0.06
	Abnormal behavior	9 (47.4)	0.14	0 (0.0)	0	0 (0.0)	0.60	9 (47.4)	0.11
Patients only (n=20)	Other than abnormal behavior	2 (10.0)	0.06	0 (0.0)	0	0 (0.0)	0	2 (10.0)	0.08
	Abnormal behavior	18 (90.0)	0.26	0 (0.0)	0	0 (0.0)	0	18 (90.0)	0.32
b. 10–19 years (n=468)
Healthcare professionals only (n=393)	Other than abnormal behavior	107 (27.2)	1.65	1 (0.3)	0.14	2 (0.5)	0.40	104 (26.5)	1.96
	Abnormal behavior	286 (72.8)	4.40	4 (1.0)	0.57	12 (3.1)	2.40	270 (68.7)	5.09
Healthcare professionals and patients (n=47)	Other than abnormal behavior	17 (36.2)	0.26	0 (0.0)	0	0 (0.0)	0	17 (36.2)	0.32
	Abnormal behavior	30 (63.8)	0.46	0 (0.0)	0	0 (0.0)	0	30 (63.8)	0.57
Patients only (n=28)	Other than abnormal behavior	4 (14.3)	0.06	0 (0.0)	0	0 (0.0)	0	4 (14.3)	0.08
	Abnormal behavior	24 (85.7)	0.37	0 (0.0)	0	0 (0.0)	0	24 (85.7)	0.45

Notes: *ADRs, such as abnormal behavior, after the administration of oseltamivir were frequently reported in the news in November 2005. **The Dear Healthcare Professional letter about abnormal behavior after the administration of oseltamivir was published by a Japanese regulatory agency on March 20, 2007.

Abbreviation: ADR, adverse drug reaction.