Try the CVS OTC product ingredients API

- `active_ingredients` and `inactive_ingredients` are the vendor's own structured active/inactive ingredient fields when upstream populates them separately. Many products leave these empty and only populate the combined `paragraph` field below — prefer `paragraph` as the more complete source. - `paragraph` is the vendor's full free-text ingredient statement. For OTC drug products this frequently also carries a Drug Facts-style purpose note (e.g. `"Active Ingredient (in each drop): Menthol, 1.5 mg - Purpose: Oral anesthetic ..."`). - Some products (particularly non-consumable goods) return empty ingredient fields alongside a valid `id`/`title` — this reflects upstream having no label data for that product, not an error. - CVS.com is only available from US/US-territory egress; a request from an unsupported region, or a page CVS blocks, returns a `503` upstream error rather than an empty or wrong result. - An unrecognized `slug` returns a `400` invalid-parameter error before any upstream request is made. A well-formed but nonexistent product id returns a `404`.