Comparison

L-Theanine Liquid and L-Theanine 200 mg

L-Theanine Liquid (NuMedica) lists 3 distinct ingredients and L-Theanine 200 mg (Superior Source) 2 (rows of one ingredient counted once); 2 are on both labels. On the site's similarity measure, which compares ingredient lists (1 for the same list, rarer ingredients counting for more; amounts are not part of it), the two formulas score 0.60.

Amount per serving (and % of the Daily Value)
IngredientL-Theanine LiquidL-Theanine 200 mg
Theanine200 mg200 mg
Stevia12.5 mg2 mg
German Chamomile40 mg

Amounts are per serving as DSLD gives them: L-Theanine Liquid, 40 drops; L-Theanine 200 mg, 2 microlingual(r) tablets. Current labels entered January 2020 and January 2020. Percentages of the Daily Value from 21 CFR 101.9. Source: NIH ODS Dietary Supplement Label Database.

Each product on its own