ODB price-ratio flags show ingredient-cost asymmetry, not therapeutic interchangeability
How to interpret a price-ratio list without turning a cost observation into a clinical recommendation.
A price-ratio flag identifies an ingredient-cost pattern. It does not decide whether a patient should change strength, split a tablet, alter a regimen, or substitute a product. The clinical decision remains separate from the pricing observation.
In public formularies, the unit price of an oral solid does not always scale linearly with strength. A higher-strength tablet may sometimes cost much less per milligram than a lower-strength tablet. That observation can help a pharmacist notice a potential cost-saving opportunity, but it is only the beginning of a review.
The ratio is a screening signal
The ratio compares the most expensive per-milligram option with the least expensive per-milligram option in the listed strengths. A high ratio says “there may be a pricing asymmetry.” It does not say “split this tablet.” Many drugs are not appropriate for splitting. Some patients cannot split tablets safely. Some regimens require a specific formulation. Some products have score-line, stability, absorption, or adherence issues.
- Confirm that the drug and strength are clinically equivalent for the patient’s regimen.
- Confirm that the dosage form can be split or substituted safely.
- Confirm whether the patient can perform the administration reliably.
- Confirm whether prescriber authorization is required.
- Document the cost rationale separately from the clinical rationale.
Why the FRx table includes a warning
The price-ratio table is intentionally narrow. It is not a therapeutic interchange guide, not a tablet-splitting endorsement, and not a formulary recommendation. Its value is in drawing attention to claims where ingredient-cost structure may deserve a closer look.
Because public formulary prices can change, the table should be treated as dated reference material. Any real intervention should be checked against the current formulary, the product monograph or professional reference, and the patient’s clinical situation.
How to document a cost observation
If a price-ratio flag leads to a clinical conversation, the note should separate the pricing observation from the patient-specific decision. The pricing note might say that the listed cost per milligram differs materially between strengths. The clinical note should separately explain why any proposed change is appropriate, who authorized it, and how the patient will administer it safely.
This separation matters because ingredient-cost logic alone does not satisfy clinical appropriateness. A cheaper per-milligram strength can still be the wrong choice for a patient because of formulation, adherence, swallowing ability, cognition, dose flexibility, or prescriber intent.
FRx guide page · Static editorial reference · Last reviewed 2026-05-02