Table 1.

Synergy assignment criteria based on Combination Index ranges.

CI	Description
<0.1	Very Strong Synergism (VSS)
0.1–0.3	Strong Synergism (SS)
0.3–0.7	Synergism (S)
0.7–0.85	Moderate Synergism (MS)
0.85–0.90	Slight Synergism (SlS)
0.90–1.10	Nearly Additive (NAdd)
1.10–1.20	Slight Antagonism (SlA)
1.20–1.45	Moderate Antagonism (MA)
1.45–3.3	Antagonism (A)
3.3–10	Strong Antagonism (SA)
>10	Very Strong Antagonism (VSA)