Table 2. The pooled adverse effects of modafinil in included studies.

Adverse effect	No. of studies	No. of patients modafinil/placebo	Risk Ratio and 95%CI	P value	I2 (%)
Insomnia	5	172 / 175	4.20 [1.52, 10.60]	0.002	0
Headache	4	160 / 163	1.19 [0.70, 2.03]	0.53	0
Dizziness	4	138 / 140	2.40 [0.71, 8.15]	0.16	0
Anxiety	3	95 / 97	1.23 [0.23, 6.72]	0.81	0
Nausea	4	136 / 138	3.79 [1.29, 11.16]	0.02	0
Diarrhea	3	108 / 110	1.21 [0.22, 6.59]	0.83	0