Anhydrous

When a clinical drug has a BoSS specified in a Summary of Product Characteristics as an anhydrous substance, the PAI is represented as the unmodified substance, i.e., the substance with an unspecified level of hydration.

Examples:

1153520006 |Product containing precisely carbidopa anhydrous (as carbidopa) 25 milligram and levodopa 250 milligram/1 each conventional release oral tablet (clinical drug)|

The SPC states each tablet "contains 27.0 mg carbidopa (equivalent to 25 mg of anhydrous carbidopa) and 250 mg levodopa." The BoSS is anhydrous carbidopa, so the PAI is Carbidopa.

1331919008 |Product containing precisely carbidopa anhydrous (as carbidopa) 12.5 milligram and entacapone 200 milligram and levodopa 50 milligram/1 each conventional release oral tablet (clinical drug)|

This SPC states, "Each film-coated tablet contains 50 mg of levodopa, 12.5 mg of carbidopa anhydrous (as 13.5 mg carbidopa monohydrate) and 200 mg of entacapone." The Boss is anhydrous carbidopa, so the PAI is Carbidopa.