. Author manuscript; available in PMC: 2019 Jul 1.

Published in final edited form as: Toxicol Pathol. 2018 May 27;46(5):564–573. doi: 10.1177/0192623318778796

Table 1.

Frequency of retinal degeneration in F344/N male and female rats treated with kava kava extract by gavage for two years (Yamashita et al. 2016). The incidence of retinal degeneration was significantly increased in a treatment-related fashion in both sexes.

2-year bioassay of Kava kava extract	Kava kava extract (g/kg)
2-year bioassay of Kava kava extract	0	0.1	0.3	1
Males
Retinal degeneration	6/45 (13%)^a ^***	7/46 (15%)	16/41 (39%)^**	23/41 (56%)^***
Females
Retinal degeneration	6/44 (14%)^*	8/46 (17%)	8/41 (20%)	14/44 (32%)^*

Fifty animals per group were initially assigned to each study; however, some animals were excluded from the assessment because of improper specimen handling, postmortem autolysis, or due to early deaths.

Note. Trend test under control column; pairwise test under dose group columns.

Significant at p < .05.

^**

Significant at p < .01.

^***

Significant at p < .001.