I don't see dilution anywhere on that page, and increasing volume of administration at a lower concentration to achieve the same effective dose does not alter the dose itself. You are not interpreting TI correctly.
Edit: further, to your comment about "prescription strength" nomenclature, look at section 14 of the Cialis/tadalafil prescribing information, IIRC, table of clinical studies, where they have the second two outcomes of the clinical studies broken down by dose. Efficacy increases pretty directly with increasing dose, and these are where the observed side effects show up. It seems like patients may well self-escalate. Maybe the OTC countries have public data on this?
NTI drugs, a/k/a critical dose drugs, can avoid titration requirements through dilution. It’s harder to fuck up a 500 mL difference than a 1 mL difference. Again, this is why most OTC versions of prescription drugs are different in only one way: concentration.
Edit: further, to your comment about "prescription strength" nomenclature, look at section 14 of the Cialis/tadalafil prescribing information, IIRC, table of clinical studies, where they have the second two outcomes of the clinical studies broken down by dose. Efficacy increases pretty directly with increasing dose, and these are where the observed side effects show up. It seems like patients may well self-escalate. Maybe the OTC countries have public data on this?